For the cake
Preheat oven to 350º
Add the dry ingredients to your stand mixer and stir to combine and break up any big lumps.
Next, add the wet ingredients, stirring a bit as you go to combine.
When the batter is all mixed, pour into a parchment lined quarter sheet pan.
Bake 25 minutes or until a toothpick inserted comes out clean, though cake will be dense and moist.
When the cake cools, flip it over onto the counter or a cutting board and remove the parchment paper carefully.
Using a biscuit cutter, pint glass, or whatever you like, cut out 2 identical pieces for each cake. You can go with a variety of sizes or make your cakes all the same.
When you start running low on cake to cut, you can push together scraps to make a “frankenlayer.” Just use that in the center of an individual cake so there is stability above and below.
Slice each layer in two to create 4 layers per cake.
For the frosting
Whip the cream cheese in your stand mixer until it is light and fluffy
Sprinkle in the cornstarch or tapioca flour while mixing on low, then turn it up when everything is incorporated
Add the vanilla and peanut butter, while continuously mixing.
Check the texture of your frosting. If you need to thin it out, add some milk, yogurt, or water. If you need it thicken it more, add a little more cornstarch or tapioca flour. Your ideal texture is whatever you will be comfortable piping, but if you’re not sure, go for a texture that holds a good peak, but still has a little flow to it.
Use an offset spatula to spackle your cake layers together. Cover the sides and top of the cake as well to hold in the crumbs and smooth out the layers.
When all your cakes are crumb coated, pop them in the fridge for an hour (or up to overnight) before piping on your decoration. This will keep your layers firmly glued together.
If you’re waiting overnight to finish your cakes you can store the frosting in the fridge. Just whip it before you pipe it to get it soft again.
When you’re ready to frost the cakes, use your favorite tip or just a nice big open star in your piping bag.
Fill your piping bag by placing it in a pint glass and folding the outside of the bag over the edges.
Use a spatula to transfer the frosting into the bag. Don’t overfill the bag, you want to be able to roll down the end very securely to ensure you don’t squeeze frosting out of both ends of the bag at once!
Once you frost your cake it will be tricky to move so you may want to cut out a cardboard base for your cake, or just set it on whatever plate you plan to serve it on for convenience.
Start frosting your cake by creating rosettes around the base of the cake.
Continue frosting petite rosettes up the side of the cake until you reach the top.
Start frosting the top of the cake from the center working outward.
You can just shoot a little frosting into any gaps you see in the rosettes.
Store your cake in the fridge until it’s time to serve!