Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a large bowl, whisk together all-purpose flour, granulated sugar, cocoa powder, baking soda, baking powder, and salt.

In a separate bowl, mix together vegetable oil, buttermilk, eggs, red food coloring, and vanilla extract until well combined.

Gradually add the wet ingredients to the dry ingredients and stir gently until just combined.

Pour in the cooled brewed coffee and stir until the batter is smooth. Avoid over-mixing.

Divide the batter evenly between the prepared pans and smooth the tops.

Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

Once baked, allow cakes to cool in the pans for about 10 minutes before transferring to wire racks to cool completely.

In a mixing bowl, beat softened unsalted butter until light and creamy.

Gradually add powdered sugar and cocoa powder, mixing until smooth and fluffy.

Add vanilla extract and brewed coffee to achieve a lighter consistency.

Once the cakes are completely cooled, place one layer on a serving plate and spread a generous amount of frosting on top.

Add the second layer and frost the top and sides of the cake.