Preheat oven to 350°F
In a stand mixer cream butter, sugar and vanilla together.
Separate egg yolk from whites, place whites in a bowl and set aside. Add yolks into the creamed butter one at a time until all are incorporated well.
Add sour cream one spoonful at a time, until all sour cream is added
Mix flour and baking powder and add into butter mixture, reserve 1-2 tablespoon to later mix with cocoa powder, and add flour into cream.
In a separate large bowl with egg whites mix with a hand mixer on high speed until stiff peaks form. Then add the egg whites to the batter and mix in by hand with a spatula.
Separate the batter evenly between 2 bowls it doesn't have to be exact just get it as close as you can.
Into one of the bowls add the cocoa powder that you mixed with the 1 tablespoon of the reserved flour and mix with a spatula until incorporated and the batter is smooth.
Prepare bundt pan by spraying with nonstick spray and then dusting with flour
Drop in 1 tablespoon at a time alternating the brown and white batter until all batter is in the bundt pan then using a chopstick or bbq stick lightly swirl the batter creating the marble effect
Place bundt pan into the preheated oven and bake for 50-55 minutes
Once bundt is baked let cool on the countertop for about 10 minutes then invert on to cake server or plate and let cool completely
While the bundt is cooling prepare the chocolate ganache
Heat 1 cup of heavy cream in a pot until simmering, place 1 cup of chocolate chips into a bowl and pour hot cream over and cover for 10 minutes. Then mix with a spatula until creamy and pour over cooled bundt cake. Let ganache settle and enjoy!
