Preheat oven to 350°F. Grease two 8-inch cake pans and line the bottoms with parchment paper rounds.

In a small bowl or measuring cup, whisk together the hot coffee and cocoa powder until smooth. Let cool slightly.

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.

In a large bowl, whisk together the eggs, sugar, oil, melted butter, vanilla, and sour cream until smooth. Add the coffee-cocoa mixture and whisk until combined.

Add the dry ingredients into the wet ingredients and gently whisk until the batter is smooth and just combined. Do not overmix.

Divide the batter evenly between the prepared cake pans.

Bake on a lower oven rack for 15 minutes, then transfer to a more centered rack position and continue baking another 10 to 15 minutes, or until a tester comes out clean.

While the cakes bake, make the frosting. Beat together the softened butter and cream cheese until smooth and creamy. Add the vanilla and salt, then gradually mix in the powdered sugar and cocoa powder until smooth and fluffy.

Let the cakes cool in the pans for about 30 minutes. Run a knife around the edges, carefully invert onto a wire rack, then carefully flip them back over so the tops remain upright. Let cool completely before frosting.

Add a small amount of frosting to the base of your serving plate to keep the cake stable. Place the first cake layer down.

Transfer the frosting to a piping bag or zip-top bag with the tip snipped off. Pipe frosting around the edge of the cake twice to create a thick border, then fill the center and smooth it out evenly. Add the second cake layer on top.

Frost the top and lightly frost the sides for a natural naked cake look.

Refrigerate the cake for a few hours so the frosting can firm up and set properly.

Trim the flowers to your desired length and wrap the stems with plastic wrap before inserting them into the cake.

Arrange the flowers organically around the cake and serve.