Step 1: Bake the Chocolate Cake

1. Preheat oven to 350°F (175°C). Grease and line two 9-inch cake pans with parchment paper.
2. In a large bowl, whisk together flour, cocoa powder, sugar, baking powder, baking soda, and salt.
3. Add eggs, buttermilk, oil, and vanilla. Mix until combined.
4. Stir in hot coffee or water (batter will be thin—this is normal).
5. Divide batter evenly between the cake pans.
6. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean.
7. Let cakes cool in pans for 10 minutes, then transfer to a wire rack to cool completely.

Step 2: Make the Strawberry Filling

1. In a small saucepan over medium heat, combine strawberries, sugar, and lemon juice.
2. Cook for 5-7 minutes, stirring occasionally, until strawberries soften.
3. Mix cornstarch with water and stir into the strawberry mixture. Simmer for 1-2 minutes until thickened.
4. Remove from heat and let cool completely before using.

Step 3: Prepare the Chocolate Buttercream

1. Beat butter in a large bowl until creamy (about 2 minutes).
2. Add cocoa powder, powdered sugar, heavy cream, vanilla, and salt. Beat until light and fluffy.
3. If frosting is too thick, add more heavy cream; if too thin, add more powdered sugar.

Step 4: Make the Ganache

1. Heat heavy cream in a small saucepan until it begins to simmer (do not boil).
2. Pour over chopped chocolate in a heatproof bowl. Let sit for 1 minute, then stir until smooth.
3. Let cool slightly before drizzling over the cake.

Step 5: Assemble the Cake

1. Place one cake layer on a serving plate. Spread a thin layer of chocolate buttercream, then spread the strawberry filling evenly on top.
2. Add the second cake layer and frost the entire cake with chocolate buttercream.
3. Pour chocolate ganache over the top, letting it drip down the sides.
4. Decorate with fresh strawberries and chocolate shavings.