01 -
Preheat oven to 350°F (177°C). Sift black cocoa powder into a mixing bowl. Add hot coffee and whisk thoroughly. Whisk in sour cream until smooth. Allow to cool completely before using.
02 -
In a stand mixer fitted with the paddle attachment, combine softened butter and sugar. Beat on low to blend, then increase speed to medium-high and cream for 2 to 3 minutes until pale and fluffy. Scrape sides as needed.
03 -
Reduce mixer speed to low and mix in vanilla and vegetable oil with one egg. Blend until incorporated, scrape down bowl, then add remaining eggs individually, mixing well between each.
04 -
In a separate bowl, whisk together 2 1/2 cups flour, baking powder, baking soda, and salt. Toss chocolate chips with remaining 1 tablespoon flour to coat.
05 -
With mixer on low, add one third of flour mixture to the butter mixture and mix until nearly blended. Add half the cooled cocoa mixture and beat until just combined. Scrape bowl and repeat, alternating dry and wet: add another third of flour mixture, then remaining cocoa mixture, then final third of flour. Mix in chocolate chips until just dispersed.
06 -
Coat a 12-cup Bundt pan with nonstick spray. Scrape batter into pan and smooth the surface. Bake for 50 to 60 minutes, or until a toothpick inserted in center comes out clean.
07 -
Transfer Bundt pan to a rack. Cool for 5 to 10 minutes, then carefully invert onto a serving platter. Let the cake cool fully to room temperature.
08 -
While cake bakes, chop white chocolate into fine pieces and place in bowl. In a saucepan over medium-high heat, combine heavy cream, corn syrup, and red gel food coloring. Bring to a boil, remove from heat, and pour over white chocolate. Let stand 5 minutes, then whisk until smooth. Cool completely; ganache will thicken and can be refrigerated if needed.
09 -
Pour cooled ganache over cake, allowing it to drip down the sides for a decorative effect. Serve immediately or chill to set the ganache.