First, prepare the cake. Butter and flour three 6" cake pans. Preheat oven to 350F.

In a stand mixer fitted with the paddle, cream together the butter, peanut butter, white and brown sugars. Cream for 3-4 minutes until light and fluffy.

Add in the eggs, one at a time, beating well between each. Mix in the sour cream and vanilla.

Add the flour, salt, and baking powder, followed by the milk.

Divide the cake batter evenly between the 3 pans, and spoon a few tablespoons of grape jelly on top. Using a knife, gently swirl the jelly into the cake batter.

Bake at 350F for 30-35 minutes, until a toothpick inserted in the center comes out clean.

Let cakes cool completely before assembly.

When ready, trim the tops of the cakes so that they are flat.

In the bowl of a stand mixer fitted with a whisk attachment, beat the butter for the frosting until smooth and creamy. Add in the powdered sugar, salt, and grape jelly. You can add more as needed to make the frosting creamy and light! Mix in purple food coloring until you reach your desired color.

To assemble, dollop a small amount of frosting on a cake platter or cardboard cake circle, and place one of the cakes on top.

Scoop your frosting into a piping bag, and pipe a thick border around the edge of the cake. Spoon some of the grape jelly in the center.

Repeat with the other two cakes. Set a small amount of frosting aside for the decorations, then spoon the rest on top of the cake. Using an offset spatula or cake scraper, frost the sides of the cake.

Refrigerate until firm before adding the ganache.

For the ganache, combine the peanut butter chips and heavy cream in a microwave-safe bowl, and heat in 15-sec intervals until smooth and creamy.

Pour the ganache into a squeeze bottle, and go around the edge of the cake, making drips as desired.

Squeeze the rest of the ganache on top of the cake to cover.

Decorate the cake as desired with the leftover frosting, sprinkles, and peanut butter chips.

Enjoy! Store leftovers in the fridge.