Preheat oven to 350°F (175°C). Grease and line two 9-inch cake pans.
In a bowl, whisk flour, sugar, cocoa powder, baking powder, baking soda, and salt.
Add eggs, oil, buttermilk, and vanilla. Mix until smooth.
Gently fold in chopped strawberries.
Divide batter into cake pans and bake for 25–30 minutes, or until a toothpick comes out clean.
Let cakes cool completely before frosting.
For frosting, whip heavy cream, then fold in melted chocolate until smooth.
Frost cake layers, stack, and garnish with fresh strawberries on top.