In a medium bowl, mix the softened butter with 3/4 cup of sugar.
Using an electric mixer, whisk the eggs with 1 cup of sugar.
Add the butter mixture into the egg mixture.
In a separate bowl, mix together the sour cream, baking powder, and baking soda. Add the sour cream mixture into the egg and butter mixture.
Working slowly, add the flour into the batter until well-combined. Next, split the batter in half in two separate bowls. Add cacao powder to one of the bowls to create the chocolate cake and whisk until well-combined.
Spray a 7-inch cake pan with cooking spray. Alternating the different colors of batter, place two tablespoon of batter at a time into the cake pan until you run out. This will create the zebra stripe effect.
Bake the cake at 350°F for 40 minutes. To check if the cake is done, stick a toothpick into the center. If it comes out clean, it's ready. Once the cake completely cools at room temperature, slice it into 2-3 equal sized layers with a serrated knife.
Soaking Zebra Cake
Soak each cake layer with about 1/2 cup of whipping cream (use a squirt bottle if you have one).
Cake Cream
Using an electric mixer, whip the heavy cream and powdered sugar together just until it reaches stiff peaks.
Apply the cream between each layer and use the remaining cream to frost the outside of the cake.
Chocolate Ganache
In a small saucepan, bring the heavy cream to a boil. Next, pour it over the chocolate chips in a medium size bowl and stir the mixture until smooth. Give the ganache a couple of minutes to cool.
Apply the ganache all over the top of the cake. If you wish, decorate the top with chocolate shavings, sprinkles, or whatever else you'd like. Eat immediately or let the cake set overnight in the refrigerator for best results. Enjoy!