Preheat your oven to 350°F (175°C). Grease and flour two 8-inch round cake pans, then line the bottoms with parchment paper.

In a large bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.

In a separate medium bowl, whisk together the buttermilk, vegetable oil, eggs, and vanilla extract.

Pour the wet ingredients into the dry ingredients and mix on low speed with an electric mixer until just combined. Gradually add the hot coffee (or water) and mix until the batter is smooth. The batter will be thin.

Divide the batter evenly between the two prepared cake pans. Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.

Let the cakes cool in the pans for 10-15 minutes before inverting them onto a wire rack to cool completely. Remove parchment paper.

While the cakes are cooling, combine the diced strawberries, granulated sugar, and lemon juice in a medium saucepan. Cook over medium heat, stirring occasionally, until the strawberries soften and release their juices, about 5-7 minutes.

Remove from heat and mash the strawberries slightly with a fork or potato masher, leaving some small chunks for texture. Let the filling cool completely.

Place the finely chopped dark chocolate (and optional butter) in a heatproof bowl. In a small saucepan, heat the heavy cream over medium heat until it just begins to simmer around the edges (do not boil).

Pour the hot cream over the chocolate. Let it sit for 5 minutes to melt the chocolate, then whisk gently from the center outwards until smooth and glossy. If using butter, it should melt in the hot cream.

Let the ganache cool at room temperature, stirring occasionally, until it reaches a thick, spreadable consistency, similar to a soft frosting. This can take 30-60 minutes, or longer if your kitchen is warm. (You can refrigerate for 15-20 minutes, stirring every 5 minutes, to speed up cooling, but be careful not to let it get too firm).

Once the cakes are completely cool, use a serrated knife to level the tops of the cakes if necessary, creating flat surfaces.

Place one cake layer on your serving plate or cake stand. Spread about half of the strawberry filling evenly over the top, leaving a small border.

Place the second cake layer on top. Spread the remaining strawberry filling on this layer, again leaving a border.

Generously frost the top and sides of the cake with the cooled chocolate ganache, using an offset spatula to smooth it out. For a 'drip' effect, ensure the ganache is still slightly warm and fluid, letting it naturally drip down the sides.

Garnish the top of the cake with fresh strawberry halves or whole strawberries and chocolate shavings.

For best slicing and flavor development, refrigerate the cake for at least 30 minutes before serving.