2 ½ cups (315g) all-purpose flour
2 ½ tsp baking powder
½ tsp salt
1 cup (225g) unsalted butter, softened
1 ¾ cups (350g) granulated sugar
4 large eggs
1 tbsp vanilla extract
1 cup (240ml) whole milk
Red, purple, orange, yellow, green, blue gel food colors
200g Bournville dark chocolate
¾ cup (180ml) heavy cream
1 tbsp unsalted butter
Preheat oven and grease six cake pans. Cream butter and sugat then add eggs one at a time. Mix in vanilla and add flour, baking powder, and salt.
Divide batter into six parts and add different food gel in each. Pour into separate cake pans and bake for 15-18 minutes.
Heat heavy cream and pour over Bournville dark chocolate. Let sit for 2 minutes and stir until well dissolved.
Stack the cake layers with ganache in between. Cover the cake with remaining ganache. Decorate the cake with sprinkles and slice it to serve.