Preheat the oven to 350°F (175°C). Spray a 9" cake pan with non-stick baking spray and set aside.

In a large bowl, whisk together 1 1/4 cups (150 g) all-purpose flour, 1/2 cup (43 g) unsweetened cocoa powder, 3/4 cup (149 g) granulated sugar, 1/2 cup (106 g) light brown sugar (packed), 1/4 teaspoon baking soda, 1/4 teaspoon baking powder, and 1/2 teaspoon salt until evenly combined.

In a separate bowl, whisk together 2 large eggs (at room temperature), 1/2 cup (99 g) vegetable oil, 3/4 cup (170 g) sour cream, 1/4 cup (57 g) milk, and 2 teaspoons vanilla extract until smooth.

Add the wet mixture to the dry mixture in three additions, folding gently with a rubber spatula each time just until incorporated. Do not overmix.

Stir in 1/3 cup (74 g) freshly brewed coffee or freshly boiled water until the batter is evenly combined; it will be thin, dark, and velvety.

Pour the batter into the prepared pan, smooth the top, and bake in the preheated oven for 45–50 minutes, or until a toothpick inserted into the center comes out clean.

Remove the pan from the oven and place it on a cooling rack. Cool in the pan for 30 minutes.

After 30 minutes, run a knife around the pan if needed, remove the cake from the pan, and cool completely on the rack before frosting.

To make the ganache, place 1 cup (170 g) finely chopped semi-sweet chocolate and 1 teaspoon espresso powder (optional) in a medium heatproof bowl.

In a small saucepan over medium heat, warm 1/2 cup (113 g) heavy cream just until it comes to a simmer (steam and small bubbles at the edge); do not let it boil. Remove from heat.

Pour the hot cream over the chopped chocolate and let sit undisturbed for 2 minutes. Stir until the mixture is smooth and glossy.

Chill the ganache in the refrigerator for 30 minutes. Then whisk gently until it becomes slightly fluffy and spreadable.

Spread the whipped ganache over the completely cooled cake. Top with shaved chocolate and fresh raspberries, if using. Serve.