Place 4 sponge cakes upside down on a cutting board and, using a serrated knife, cut off a ¼-inch thick disc from each and discard (or eat!) the remaining cake pieces. Set cake discs aside.

In a small bowl, stir together ½ cup of the vanilla pudding and the matcha powder until well combined.

In another small bowl, stir together the remaining ½ cup vanilla pudding and the peanut butter until well combined.

To assemble the strawberry-matcha cakes: Fill 2 sponge cups with the matcha pudding mixture and 2 sponge cups with strawberry jam. Place a cake disc on top of each matcha cup, then invert the strawberry sponge cups on top. Set aside and label to remember the flavor.

To assemble the chocolate-peanut butter cakes: Fill 2 sponge cups with the peanut butter pudding mixture and 2 sponge cups with chocolate pudding. Place a cake disc on top of each peanut butter cup, then invert the chocolate cups on top. Set aside and label to remember the flavor.

Using a serrated knife, trim the sides of the cakes to even out the edges, if needed. Coat each cake with a very thin layer of vanilla frosting to hold loose crumbs in place and even out the edges. Chill in the refrigerator for 10 minutes.

Meanwhile, divide the remaining frosting into 4 small bowls and use food coloring to create one bowl each of pink, green, light brown and dark brown frosting.

Frost and decorate the strawberry-matcha cakes with the pink and green frosting, and the chocolate-peanut butter cakes with the brown frostings.

Leftover cakes can be stored in an airtight container in the refrigerator for up to 3 days.