Chocolate Chip Bundt® Cake

Preheat the oven to 300 degrees F (150 degrees C). Grease and flour a 12-cup fluted tube pan (such as a Bundt® pan) to ensure the cake releases easily. (Prep time: 10 minutes)

In a large bowl, cream together the sugar and margarine with an electric mixer until light and fluffy. This step is crucial for a tender crumb. Add the eggs one at a time, beating well after each addition. Then, mix in the sour cream and vanilla extract until just combined. (Mixing time: 8 minutes)

In a separate bowl, sift together the flour, baking soda, and baking powder. Sifting ensures there are no lumps and distributes the leavening agents evenly. Gradually add the dry ingredients to the wet ingredients in four batches, beating until just combined after each addition. Be careful not to overmix, as this can result in a tough cake. (Mixing time: 5 minutes)

Divide the batter. In a separate bowl, remove about 2 1/2 cups of the batter and mix in the cocoa powder until well combined, creating a rich chocolate batter. Stir in the white chocolate chips into this chocolate batter. (Mixing time: 5 minutes)

Gently stir the dark chocolate chips into the remaining light-colored batter. (Mixing time: 2 minutes)

Layer the two batters into the prepared Bundt® pan, alternating between the light and dark batters. Start with the light-colored batter to prevent the darker batter from sinking to the bottom. Swirl the batters gently with a knife or skewer for a marbled effect, if desired. (Layering time: 5 minutes)

Bake in the preheated oven until the top is golden brown and a toothpick inserted into the center comes out clean. This should take approximately 1 hour and 20 minutes. Begin checking for doneness around the 1 hour 10-minute mark to prevent overbaking. (Baking time: 1 hour 20 minutes)

Let the cake cool in the pan on a wire rack for 20 minutes before inverting it onto a serving plate. Run a thin knife or spatula around the edges of the pan to loosen the cake before inverting. (Cooling time: 20 minutes)