Heart Cake

For the cake

1. Preheat the oven to 325 degrees F. Coat two 9-inch cake pans with cooking spray and line the bottom and sides with parchment paper. Soak the cake baking strips in water.
2. Sift the flour, cocoa powder, baking powder, baking soda, and salt into the bowl of a mixer, then stir in the sugar.
3. In a separate bowl, use a whisk or hand blender to combine the buttermilk, vegetable oil, eggs, vanilla, vinegar, diluted coffee, and red food coloring. If desired, add more food coloring for a more intense red color.
4. Turn the mixer to low speed. Slowly mix the wet ingredients into the dry ingredients until the mixture is just combined. Be careful not to overmix your batter.
5. Pour the batter evenly between the two pans. You can use a kitchen scale to measure the pans to make sure they have the same amount of batter.
6. Squeeze out the excess water from the baking strips and secure then around the cake pans.
7. Bake for 60-65 minutes, or until the cakes are springy to touch and a toothpick comes out clean or with a few crumbs attached.
8. Let the cakes cool in the pans for 20 minutes, then carefully invert the cakes onto a cooling rack, and cool completely.

For the frosting

1. Beat the butter and vanilla extract together with a stand mixer or electric mixer for 1-2 minutes or until light and fluffy.
2. Reduce the mixer speed to low and add the powdered sugar, 1 cup at a time, until everything is combined.
3. In a separate bowl beat the cream cheese until smooth. This step ensures there are no lumps of cream cheese in the frosting.
4. Add the cream cheese to the frosting mixture and beat until combined. It should be smooth and creamy and have a medium-thick consistency. Set aside 1 ½ cups to pipe a border on the cake.

For the heart shape

1. Trim the tops off the cakes with a large, serrated knife or cake leveler to create flat, even layers.
2. Place one cake layer on your cake stand or serving plate close to the bottom edge. Pipe a thin layer of frosting over the cake layer, then add the second layer on top.
3. To create the heart shape, use a large, serrated knife to score a cross on the top of the cake.
4. On each side, cut a wedge from the cake diagonally from the bottom point to the horizontal point on each side.
5. Turn the wedges on their sides with the cut side facing upwards. Pipe frosting onto them, then press each firmly onto the top side of the cake to form the mounds of the heart. If desired, cut a small ‘v’ into the cake between the mounds to accentuate the shape.
6. Use an offset spatula to apply a crumb coat to the cake. Chill for 30 minutes. This helps to prevent any red crumbs in the final layer of frosting and provides a firm base to apply the frosting.

For the decorating

1. Pipe more frosting onto the top and sides of the cake and use a cake scraper to create a smooth finish. 
2. Place a large star nozzle into a piping bag and fill with the reserved frosting.
3. On the top of the cake, pipe a bulb of frosting at the top of one of the mounds and ease the nozzle back diagonally to form a tail. Position the nozzle slightly lower than the first and pipe another bulb and pull back to create another tail. Continue to pipe a border around the top of one side of the cake ensuring each bulb just touches the previous bulb. Repeat on the other side.
4. Decorate as desired with sprinkles, then cut into slices, and serve.