Preheat the oven to 340 degrees Fahrenheit or 170 degrees Celsius.

Grease a 6-inch baking pan with nonstick spray or butter and line it with parchment paper.

In a mixing bowl, add 100 grams of Dark Chocolate, 1/3 cup of hot whole milk, and 1/4 cup of unsalted melted butter.

Then, whisk until the mixture is smooth.

Add 1/4 cup of granulated sugar and mix again.

Take a sieve, add 1/4 cup of all-purpose flour and 1/4 cup of cocoa powder, and sift to the brownie cake batter.

Sprinkle 1/2 tsp of salt into the batter.

Whisk the ingredients together until well combined.

In a separate mixing bowl, crack 3 large eggs and remove the yolks from the whites.

Then, pour the egg yolks into the chocolate batter.

Add 1 tsp of vanilla essence to the mixture, then whisk all of them until well combined and set aside.

Now, take the bowl of 3 room temperature egg whites you crack earlier.

Pour 1/2 tsp Vinegar into the bowl.

Use an electric beater to beat the egg whites until it’s foamy.

Then add the remaining 1/4 cup of granulated sugar and beat until stiff peaks form.

Then, using a spatula, mix some meringue with the chocolate batter you prepared with the whisk.

Then add all the meringue into the batter and fold them by using a spatula until combined.

Pour the batter into the prepared cake pan and spread it evenly.

Bake the cake in the preheated oven for 25-30 minutes.

Once baked, remove the cake from the oven and allow it to cool inside the pan for 30 minutes.

Transfer the cake to a wire rack to cool completely.

Place 100 grams of semi-sweet dark chocolate in a heatproof bowl.

Pour 1/2 cup of hot Heavy cream over the chocolate and let it sit for 2 minutes to allow the chocolate to melt.

Stir the mixture with a spoon until the ganache turns smooth and glossy.

Once the cake has cooled completely, then remove the parchment paper and pour the chocolate ganache over the top. Use a spatula to spread it evenly.