Prep the pans and oven. Heat oven to 350°F (175°C). Grease two 8-inch round cake pans, line bottoms with parchment, then lightly grease and flour the parchment and sides.

Whisk dry ingredients. In a large bowl, whisk flour, cocoa, baking powder, baking soda, and salt until uniform. This prevents lumps and ensures even rise.

Combine sugars and wet ingredients. In another bowl, whisk granulated sugar and brown sugar with eggs until slightly thickened, about 30 seconds. Add oil, buttermilk, Greek yogurt, and vanilla. Whisk until smooth.

Bring in the dry mix. Add the dry ingredients to the wet mixture. Stir gently with a spatula until a few streaks of flour remain. Do not overmix.

Add hot coffee. Pour in the hot coffee (or hot water). Stir carefully until the batter is smooth and glossy. It will be thin; that’s what makes the crumb tender.

Divide and bake. Pour batter evenly into prepared pans. Bake for 24–28 minutes, or until a toothpick comes out with a few moist crumbs. Do not overbake.

Cool completely. Let cakes cool in pans 10 minutes. Turn out onto a rack, peel off parchment, and cool fully before frosting.

Make the frosting. Beat cream cheese and butter until creamy and lump-free, 1–2 minutes. Sift in powdered sugar and cocoa; add vanilla and salt. Beat until smooth. Mix in melted, cooled dark chocolate. Adjust texture with milk or cream, 1 teaspoon at a time, until spreadable.

Assemble the cake. Place one layer on a plate. Spread about 1/3 of the frosting over the top. Set the second layer on top and frost the top and sides with the remaining frosting. Use an offset spatula for clean edges.

Finish and rest. For neat slices, chill the frosted cake 20–30 minutes before cutting. Garnish with berries or chocolate shavings if you like.