Preheat oven to 350°F (180°C). Line the cake pan with parchment paper and coat with nonstick spray.

Combine 1½ cups of chopped chocolate and butter in a microwave‑safe bowl. Microwave 30 seconds, stir, then in 20‑second intervals until smooth. Set aside to cool slightly.

In a bowl, whisk whole eggs, yolks, brown sugar, and granulated sugar until light in color and slightly thickened.

Whisk in cocoa powder, vanilla, espresso powder, and salt until uniform.

Slowly pour melted chocolate into the egg mixture while whisking until fully incorporated.

In a separate bowl, beat heavy cream to medium‑stiff peaks.

Gently fold whipped cream into batter until even; batter will be thick.

Transfer batter to prepared pan. Bake 25-30 minutes until an instant‑read thermometer in the center reads 200° F (93° C) or a toothpick yields moist crumbs.

Let the cake rest 30 minutes. Run a knife around edges, invert onto a tray, and let cool completely.

Pour ganache over the cooled cake, spreading evenly. Chill for at least 2 hours.

Top with raspberries and mint leaves if desired. Store in an airtight container in the refrigerator.