Prepare the Cake:

1. Preheat the Oven: Preheat the oven to 375°F (190°C). Grease an 8-inch round cake pan and line the bottom with parchment paper for easy removal.
2. Melt the Chocolate and Butter: In a medium saucepan over low heat, melt the chopped chocolate and butter together, stirring occasionally until smooth. Remove from heat and allow it to cool slightly.
3. Mix the Sugar and Eggs: In a separate large bowl, whisk the eggs, sugar, vanilla extract, and salt until fully combined and slightly frothy.
4. Combine the Ingredients: Gradually pour the melted chocolate mixture into the egg mixture, stirring gently until fully combined. Be careful not to overmix.
5. Pour the Batter into the Pan: Pour the cake batter into the prepared cake pan, spreading it evenly with a spatula.

Bake the Cake:

6. Bake: Place the pan in the oven and bake for 20-25 minutes. The cake will rise slightly and form a thin crust on top. It’s done when a toothpick inserted into the center comes out with only a few moist crumbs (not wet batter).
7. Cool: Allow the cake to cool in the pan for 10-15 minutes before transferring it to a wire rack to cool completely.

Serve and Garnish:

8. Remove the Cake from the Pan: Once the cake is cool, carefully run a knife around the edges of the pan to loosen the cake. Invert the cake onto a plate and peel off the parchment paper.
9. Garnish and Serve: Dust the cooled cake with powdered sugar, and top with fresh berries or whipped cream, if desired. Slice into wedges and serve chilled or at room temperature.