Combine 100g unsalted butter, 70g brown sugar, and 80-100g dark chocolate in a bowl and melt them using a double boiler. Adjust chocolate quantity to taste.

Add 2 eggs and a few drops of vanilla essence to a separate bowl and whisk well.

Pour the melted chocolate mixture into the egg mixture and mix thoroughly.

Sift 50-60g cake flour and add 1g baking powder and a handful of nuts to the batter. Mix until combined.

Pour the batter into your desired mold. Grease the mold with butter for easy removal.

Bake at 180°C for 20-25 minutes. Adjust baking time based on mold size and batter thickness.

Cool completely and cut into desired sizes.