Preparation

• Gather all ingredients. Preheat the oven to 350 degrees F (175 degrees C). Butter and flour two 9x2-inch round cake pans.
• Sift flour, sugar, cocoa powder, baking soda, baking powder, and salt together in a bowl; set aside.
• Whisk eggs in a large bowl until smooth. Add oil, buttermilk, sour cream, food coloring, vanilla extract, and vinegar; whisk until combined.
• Add flour mixture in 3 batches, mixing by hand as little as possible so as not to over beat. If using an electric mixer, add flour mixture and mix until just incorporated. Divide batter between the prepared pans.
• Bake in the preheated oven until a toothpick inserted into centers comes out clean, 35 to 40 minutes.
• Cool in the pans for 10 minutes, then remove from pans to cool completely on a wire rack, 20 to 30 minutes more.
• Meanwhile, whip cream cheese in a bowl using an electric mixer on high speed until light and fluffy, about 5 minutes. Scrape into a different bowl.
• Sift remaining sugar, flour, and salt together in a medium saucepan. Heat over medium-high heat; slowly whisk in milk and vanilla extract until there are no lumps. Cook until starts to bubble and becomes thick and pudding-like, 7 to 8 minutes.
• Pour into a bowl; refrigerate for 10 minutes.
• Whisk chilled milk mixture with an electric mixer fitted with the whisk attachment for 5 minutes. Slowly add whipped cream cheese, whisking until frosting becomes smooth, about 5 minutes.
• Frost cooled cake. Enjoy!