Brownie base

• Roast the hazelnuts in the oven for about 10 minutes.
• Prepare a baking pan by lining it with parchment paper.
• Preheat the oven to 175°C (345°F) 10 minutes before using.

1. Melt the unsalted butter and chocolate together in a double boiler or in the microwave. Add the granulated sugar and mix until dissolved.
2. Add the eggs and mix them in. It's okay to mix them briefly, just enough to combine.
3. Sift in flour and add hazelnuts.
4. Pour the mixture into a 13cm (5-inch) pan and bake in a 175°C (345°F) oven for about 15 minutes. (If you don't have an exact 13cm pan, you can use a slightly larger one and then cut out a 13cm circle using a pastry ring or cutter.)

Chocolate cream

• Line a 15cm (6-inch) pan with reusable parchment paper.
• Place the brownie in the center of the pan.
• Soak a generous amount of sheet gelatin in cold water to soften. If using powdered gelatin, sprinkle 2 teaspoons (10ml) of water over it to bloom.

1. In a bowl, mix egg yolks and granulated sugar.
2. In a saucepan, combine the milk and heavy cream and heat it up. Pour half of this mixture into the egg yolks and granulated sugar, then mix them together.
3. Return the mixture back to the saucepan and heat it again. While stirring continuously and scraping the bottom of the pan with a silicone spatula, thicken the mixture. The desired consistency is reached when the cream lightly coats the back of the spatula, when it moves in one direction and doesn't immediately flow back, or when it reaches a temperature of around 80-85°C (176-185°F). using a thermometer.
4. Remove the heat (since residual heat will continue to warm the mixture) and quickly mix in the squeezed gelatin until it dissolves.
5. Pour the melted chocolate into the mixture in 2-3 additions, and gently mix it in.
6. Pour the chocolate mousse over the brownie base in the pan. Place it in the freezer to chill and set.

Chocolate glaze

• Prepare a cake cooler and place a tray underneath.

1. Melt the chocolate in a bowl. In a separate pot, heat water, granulated sugar, and heavy cream.

   Slowly pour the mixture into the melted chocolate, stirring gently until it becomes glossy. Strain the mixture into a container for easy pouring.

2. Remove the cake from the freezer and gently remove it from the mold, applying a warm towel around the edges of the mold if needed.
3. Pour the glaze onto the cake in a circular motion, starting from the center and moving outward. Pay special attention to the sides of the cake, as they can be more challenging to coat with the glaze.
4. Once you have finished glazing, quickly transfer the cake to a serving plate before the glaze sets. To do this without damaging the glaze, you can use two long palette knives or knives crossed over each other to lift and transfer the cake from the bottom.
5. After transferring the cake to the serving plate, place it in the refrigerator to thaw for about 1 hour.