Step 1

Butter and line the bottom and sides of your pan. If you have a pastry ring, just butter and line the sides. Set aside.

Step 2

In a medium saucepan, add the milk, cocoa powder, sugar, butter, and the 25g/1oz chopped chocolate. Whisk continuously over medium heat and bring to a boil. When it starts boiling, lower the heat and let it simmer for 5 minutes while whisking. It’s important not to stop whisking so the mixture doesn’t burn. After about 5 minutes, it will thicken slightly.

Step 3

Remove the saucepan from the heat and whisk in the vanilla and the cognac (if using). Set it aside to cool a bit.

Step 4

In a large bowl, use your hands to break the cookies into medium and small pieces.

Step 5

Pour the chocolate mixture over the cookie pieces. Add half of the nuts (½ cup/50g) and stir everything with a rubber spatula or large spoon. Make sure to coat everything well.

Step 6

Transfer the mixture to the prepared pan and press it in using the spatula or the back of a spoon. Even out the surface. Refrigerate the cake for about 30 minutes.

Step 7

Heat the cream in a small saucepan until it just begins to boil and tiny bubbles appear on the sides of the saucepan. Don't boil it.

Step 8

Pour the hot cream over the chopped chocolate (150g) and let it sit for 5 minutes without stirring. After 5 minutes, stir the mixture until it’s smooth and creamy and the chocolate has melted.

Step 9

Take the cake out of the refrigerator and pour the ganache on the top. Use the back of a spoon to spread it evenly.

Step 10

Add the remaining nuts on top.

Step 11

Cover the cake loosely with plastic wrap and refrigerate it overnight. This is the most important step! The cake needs to be refrigerated overnight to solidify properly and allow all the flavors to develop.

Step 12

Unlatch the pan and remove the parchment paper. Slide the cake onto a plate or cake stand.

Step 13

Enjoy!