¼ cup heavy cream plus more if needed for desired consistency
MAKE THE CAKE:
Spray a 9×13 baking pan with cooking spray. Preheat the oven to 350 degrees Fahrenheit.
Put flour, sugar, cocoa, baking powder, baking soda and salt in a bowl and whisk well.
In a stand mixer, mix the buttermilk, oil, eggs, vanilla together. Slowly add in the mix of dry ingredients while the mixer is on low. Add the coffee and make sure everything is combined. The batter will be very thin.
Pour the batter into the prepared pan and bake for about 30-35 minutes or until the center of the cake springs back when you touch it.
Allow the cake to cool on a cooling rack. While the cake is cooling, make the frosting
MAKE THE FROSTING:
Place the freeze dried strawberries into a food processor and pulse until it makes a fine powder.
In a stand mixer bowl, with the mixer on medium speed, whip the butter for 2 minutes until it is almost white in color. Make sure the butter is at room temperature, but not melted.
Add in the powdered sugar, strawberry powder, vanilla and cream.
Beat on low speed for 3-5 minutes, adding in another tablespoon of milk if the buttercream needs to be thinner.
Spread the frosting on the cooled cake.
Garnish with strawberries and chocolate shavings or curls.