Skip to Content

Frankenstein Cake

This Frankenstein cake is the perfect Halloween dessert! It’s made with moist green velvet cake layers and cream cheese buttercream frosting.

image of a cute Frankenstein cake made for halloween

How to Make a Frankenstein Cake: Step-by-Step Tutorial

Let’s walk through each step of this Frankenstein cake together to make sure it turns out as amazing as possible!

Step 1: Bake the Green Velvet Cake Layers

Preheat your oven to 350 degrees F / 175 degrees C. Grease four, 6-inch or three, 7-inch cake pans with homemade cake release or non-stick baking spray and parchment paper.

Divide the batter evenly between the prepared pans and bang the pans on your counter a few times to release any air bubbles that might be trapped in the batter.

image of green velvet cake batter being poured into a 7 inch cake pan

Bake for 28-32 minutes, or until a toothpick inserted in the center of the cake comes out with a few moist crumbs. Remove the pans from oven and let them cool for 10 minutes then run a small offset spatula around perimeter.

Carefully flip the layers out of their pans and place on a wire rack to finish cooling. Level the cake layers with a serrated knife once they’re fully cooled. It takes a little extra time, but it makes stacking and frosting the cake layers so much easier!!

image of a green velvet cake layer being leveled

If you’re making these in advance, wrap and freeze them at this point.

Step 2: Make the Cream Cheese Buttercream Frosting

While the cake layers bake and cool, make the cream cheese buttercream frosting with either an electric hand mixer or a stand mixer. If you don’t like cream cheese frosting use additional butter in place of the cream cheese in this frosting recipe.

If your frosting seems too thick after mixing your ingredients, add in additional cream (1 tablespoon at a time). Or if the frosting is too thin, add in more powdered sugar (quarter of a cup at a time).

image of vanilla buttercream being mixed in a kitchen aid mixer

If you’re unsure how thick your frosting should be, you can learn what consistency you’re looking for in my frosting consistency post.

Once the frosting reaches the desired consistency, place 1/4 cup of frosting in a small piping bag fit with a large round tip and set aside.

Scoop 1/4 cup of frosting in a separate bowl and color grey with a tiny drop of black gel food coloring. Place in a small piping bag fit with a large round tip and set aside.

Add green food coloring to the remaining frosting and mix until the frosting is a bright shade of green. This frosting will be used to fill and cover the cake. You can either cover this buttercream with plastic wrap or place it in a large piping bag.

image of buttercream frosting in piping bags that's been colored using gel food coloring to make vibrant shades

Step 3: Stack and Crumb Coat the Cake Layers

Stack and frost the cake layers on a greaseproof cake board. Use a dab of frosting to help stick the first cake layer to the board. Spread an even layer of frosting between each cake layer.

Add a thin coat of frosting around the cake that fully covers the cake layers.

image of a cake being crumb coated in bright green buttercream

Smooth using an offset spatula and/or bench scraper. Chill the cake in the fridge (20 minutes) or freezer (5 minutes) until the frosting is firm to the touch.

Step 4: Add a Second Layer of Frosting

Remove the cake from the fridge or freezer and cover the cake in a thick, second layer of green frosting. Smooth using an offset spatula and bench scraper.

image of a cake being frosted with a second thicker layer of bright green American buttercream

Step 5: Bringing this Frankenstein Cake to Life

While the cake chills, color the remaining buttercream black. Mix in black gel food coloring and 3 Tbsp of dark cocoa powder. Place in a piping bag fit with a small round piping tip like a Wilton 12 frosting tip.

Remove the cake from the fridge or freezer. Pipe on Frankenstein’s eyes, smile, and hair using black and white buttercream. Use the grey frosting to add his neck bolts then enjoy!

image of a cute Frankenstein cake made for halloween

Substitutions and Swaps – Green Velvet Cake Layers

This Frankenstein cake recipe uses quite a few ingredients and I know you might not have all of them on hand. Or if you have food allergies or restrictions, I’ve got you covered.

Below are some swaps and substitutions that can be made in this cake recipe.

  • Cake Flour – This recipe turns out best with cake flour, but you can use a gluten free flour blend if that’s all you have on hand. Or if you can’t find cake flour you can make your own using this technique.
  • Granulated Sugar – I do not recommend reducing the amount of sugar or changing the type of sugar, as it will change the texture of the cake layers.
  • Unsalted Butter – If you only have salted butter on hand you can use it in place of the unsalted butter in this recipe. Just be sure to omit the salt that this cake recipe calls for. You can also use vegan butter in its place (and also omit the salt)!
  • Eggs – If you have an egg allergy you can try using flaxseed eggs or an egg replacer but it will affect the texture of the layers.
  • Buttermilk – You can also use full fat yogurt, sour cream, whole milk, or an alternative yogurt or milk (almond, soy, oat) if you’re dairy free.
  • Vegetable Oil – You can use any flavorless oil in this recipe. Canola or even sunflower oil would work great!
image of green velvet cake batter being mixed

Substitutions and Swaps – Cream Cheese Buttercream Frosting

  • Unsalted Butter – If you only have salted butter on hand, you can use it in place of the unsalted butter. Just be sure to omit the salt that this frosting recipe calls for. You can also use vegan butter in its place (and omit the salt)!
  • Heavy Cream – Whole milk or alternative milk (soy, almond, oat) will work fine in this frosting recipe if that’s what you have on hand.
  • Cream Cheese – If you don’t like cream cheese frosting, you can use additional butter in place of the cream cheese. Or if you want to use a less sweet frosting, try my Swiss meringue buttercream or my Russian buttercream.
  • Gel food coloring – Natural food coloring or liquid food coloring can be used if needed to color the frosting. However, I find gel food coloring works best!
image of a cute Frankenstein cake made for halloween

Tips for Making the Best Frankenstein Cake:

  • Be sure to properly measure your flour (spoon into the cup measure, then level) or use a kitchen scale to measure your dry ingredients.
  • Ingredients at room temp mix together better! Be sure you set out any cold ingredients ahead of time.
  • Use gel food coloring to create brightly colored frosting. It works best because it doesn’t throw off the consistency of the frosting or give it a bitter taste.
  • Mix your cake batter just until the ingredients are incorporated. This will ensure your cake layers are tender and fluffy.
  • Use a scale to weigh your cake pans as you fill them. Make sure each pan has the same amount of batter will make your cake layers bake to the same heigh and bake more evenly.
  • Bang your cake pans on the counter before putting it in the oven. This brings any air bubbles that are trapped in the batter to the surface.
  • Level your room temperature or thawed cake layers with a serrated knife to make them easier to stack.
  • Chill your cake layers in the freezer for about 20 minutes before assembling the cake. It makes it so much easier to trim, stack and frost them!
  • Use a circle cutter or small glass to help you space out Frankenstein’s eyes. This also makes sure they’re centered and the same size.
  • Make this Frankenstein cake vegan or dairy free if needed! Use your favorite dairy free milk to replace the buttermilk and heavy cream and vegan butter sticks in place of the butter. For the eggs I recommend using an egg replacer like this.

Making this Frankenstein Cake in Advance & Storage Tips:

  • Make your cake layers in advance and freeze them. It breaks the process up and make it more approachable.
  • Make your frosting ahead of time too or save any leftover frosting. It can be stored in an airtight container in the fridge for up to 2 weeks. Or store it in the freezer for up to a month! Be sure to give it a good stir once it thaws to get the consistency smooth again.
  • A frosted cake can last in the fridge for up to a week. The buttercream locks in all the moisture, keeping the cake fresh and delicious.
  • If you cut into the cake and have leftovers, use any remaining frosting to cover the cut section to keep it moist. It can be stored in the fridge like this for up to a week.
  • If you freeze the cake, transfer it the fridge overnight then bring to room temperature the following day. This helps prevent condensation by minimizing the temperature shock.

Let Me Know What You Think!

If you try this Frankenstein cake recipe, I’d love to hear what you think of it! Let me know by leaving a rating below.

If you share on social media, tag me @chelsweets and use #chelsweets so I can see your amazing creations!

Other Recipes You Might Like:

Yield: 20

Frankenstein Cake

image of a cute Frankenstein cake made for halloween

This Frankenstein cake is the perfect Halloween dessert! It's made with moist green velvet cake layers and cream cheese buttercream!!

Prep Time 20 minutes
Cook Time 28 minutes
Additional Time 1 hour
Total Time 1 hour 48 minutes

Ingredients

Green Velvet Cake

  • 2 1/2 cups cake flour (300g)
  • 2 Tbsp unsweetened cocoa powder (10g)
  • 1 tsp baking soda (6g)
  • 1/2 tsp salt (3g)
  • 1/2 cup unsalted butter, room temperature (113g)
  • 1 3/4 cups granulated sugar (350g)
  • 2 large eggs, room temperature (112g)
  • 1 1/4 cups buttermilk, room temperature (300g)
  • 2/3 cup vegetable oil (145g)
  • 2 squirts of green gel food coloring (or 1 Tbsp liquid food coloring)
  • 2 tsp vanilla extract (8g)
  • 1 tsp white vinegar (4g)

Cream Cheese Buttercream Frosting

  • 1 1/2 cups unsalted butter, room temperature (339g) - 3 sticks
  • 1/2 cup full-fat cream cheese, room temperature (113g or 4 oz.)
  • 1 Tbsp vanilla extract (12g)
  • 1 tsp salt (6g)
  • 8 cups powdered sugar (1000g)
  • 2 Tbsp heavy cream or whipping cream (30g)
  • Electric Green Gel Food Coloring
  • Black Gel Food Coloring

Additional Tools / Decorations

Instructions

Green Velvet Cake:

  1. Preheat oven to 350 degrees F / 175 degrees C. Grease four 6-inch or three 7-inch cake pans with homemade cake release or non-stick baking spray and parchment paper. Set aside.
  2. In a medium bowl, sift together the cake flour, cocoa powder, baking soda and salt.
  3. In a large bowl or the bowl of a stand mixer, use either a hand mixer or a stand mixer to cream together the butter and granulated sugar. Mix on a medium high speed for 1-2 minutes, until the mixture becomes lighter in color. Scrape the sides and bottom of the bowl as needed with a rubber spatula.
  4. Mix in the eggs on a medium speed until fully incorporated.
  5. Add in the buttermilk, oil, green gel food coloring, vanilla extract, and white vinegar. Mix on a low speed until combined. The mixture might look broken at this stage but I promise it will come together once we add in the dry ingredients.
  6. Slowly mix in the dry ingredients into the wet ingredients a low speed in two installments. Mix until just combined and you can no longer see any visible streaks of cake flour.
  7. Divide the batter evenly between the prepared pans and bang the pans on your counter a few times to release any air bubbles that might be trapped in the batter. Bake for 28-32 minutes, or until a toothpick inserted in the center of the cake comes out with a few moist crumbs.
  8. Remove the pans from oven and let them cool for 10 minutes then run a small offset spatula around perimeter. Carefully flip the layers out of their pans and place on a wire rack to finish cooling.
  9. Level the cake layers with a serrated knife once they're fully cooled.
  10. If you're making these in advance, wrap and freeze them at this point.

Cream Cheese Buttercream Frosting:

  1. Beat the butter and cream cheese on a medium speed for 30 seconds with a paddle attachment until smooth. If you don't like cream cheese frosting use additional butter in place of the cream cheese in this frosting recipe.
  2. Add in the vanilla and salt, and beat on low until the ingredients are fully incorporated.
  3. Slowly mix in the powdered sugar and heavy cream on a low speed. Place a kitchen towel over your mixer to prevent powdered sugar clouds from coating your kitchen. Scrape the sides and bottom of the bowl as needed with a rubber spatula.
  4. If the frosting is too thick, add in additional cream (1 Tbsp at a time). If the frosting is too thin, add in more powdered sugar (1/4 cup at a time).
  5. Once the frosting reaches the desired consistency, place 1/4 cup of white frosting in a small piping bag fit with a large round tip and set aside.
  6. Place 1/4 cup of frosting in a separate bowl and color light grey with a tiny drop of black gel food coloring. Place in a small piping bag fit with a large round tip and set aside.
  7. Add the green food coloring to the remaining frosting and mix until the frosting is a bright shade of green and evenly colored.
  8. Cover the frosting with a piece of plastic wrap to prevent a crust from forming and set aside.

Decorating this Frankenstein Cake:

  1. Stack and frost the cake layers on a greaseproof cake board. Use a dab of frosting to help stick the first cake layer to the board. Spread an even layer of frosting between each cake layer.
  2. Add a thin coat of frosting around the cake that fully covers the cake layers. Smooth using an offset spatula and/or bench scraper, then chill the cake in the fridge (20 minutes) or freezer (5 minutes) until the frosting is firm to the touch.
  3. Remove the cake from the fridge or freezer and cover the cake in a thick, second layer of green frosting. Smooth using an offset spatula and bench scraper.
  4. Chill the cake in the fridge (30 minutes) or freezer (10 minutes) one more time until the frosting is completely firm to the touch.
  5. While the cake chills, color the remaining buttercream black using gel food coloring and 3 Tbsp of dark or black cocoa powder. Place in a piping bag fit with a coupler and small round piping tip like a Wilton 12 frosting tip.
  6. Remove the cake from the fridge or freezer. Pipe on Frankenstein's eyes, smile, and hair using black and white buttercream. Use the grey frosting to add his neck bolts then enjoy!

Notes

My Tips for Making the Best Frankenstein Cake

  • Ingredients at room temp mix together better! Be sure you set out any cold ingredients ahead of time.
  • Be sure to properly measure your cake flour (spoon into the cup measure, then level). Or better yet, use a kitchen scale to measure your dry ingredients.
  • Use gel food coloring to create brightly colored frosting. It works best because it doesn't throw off the consistency of the frosting or give it a bitter taste.
  • Mix your cake batter just until the ingredients are incorporated. This will ensure your cake layers are tender and fluffy.
  • Use a scale to weigh your cake pans as you fill them. Make sure each pan has the same amount of batter will make your cake layers bake to the same heigh and bake more evenly.
  • Bang your cake pans on the counter before putting it in the oven. This brings any air bubbles that are trapped in the batter to the surface.
  • Level your room temperature or thawed cake layers with a serrated knife to make them easier to stack.
  • Chill your cake layers in the freezer for about 20 minutes before assembling the cake. It makes it so much easier to trim, stack and frost them!
  • Use a circle cutter or small glass to help you space out Frankenstein's eyes. This also makes sure they're centered and the same size.

Making this Frankenstein Cake in Advance & Storage Tips

  • Make your cake layers in advance and freeze them. It breaks the process up and make it more approachable.
  • Make your frosting ahead of time or save any leftover frosting! It can be stored in an airtight container in the fridge for up to a month.
  • This frosting can also be stored in the freezer for up to 3 months! Just be sure to give it a good stir once it thaws to make it nice and smooth again.
  • A frosted cake can last in the fridge for a week, or in the freezer for a month. The buttercream locks in the moisture and keeps the cake fresh and delicious!

Nutrition Information

Yield

20

Serving Size

1

Amount Per Serving Calories 611Total Fat 31gSaturated Fat 15gTrans Fat 0gUnsaturated Fat 14gCholesterol 88mgSodium 333mgCarbohydrates 81gFiber 1gSugar 65gProtein 4g

Samantha

Thursday 21st of October 2021

Hi! I was wondering if I could use 100% Blue Agave instead of granulated sugar. The bottle says 1 cup is equal to 1 1/2 cups of sugar. So I wanted to make sure I could do it for any of your cake recipes. Would it change the texture do you think? Thanks so much! :)

Skip to Recipe