Stir by hand with a rubber spatula to get the frosting SUPER smooth, then place 2/3 of the vanilla buttercream a medium-sized bowl. Color it a golden shade of yellow using gel food coloring. Use either egg yellow gel food coloring, or a combination of yellow and orange gel food coloring. Place this into a small piping bag fit with a leaf tip piping tip (like a
Wilton 352) and set aside.