1- First of all, put your all ingredients on the work surface. Then, use your hands to crumble the your petit beurre biscuits into small squares and set aside.

2- Then in a saucepan, melt the butter. Then pour butter into a large mixing bowl and then add cocoa powder and granulated sugar into the melted butter and mix them very well (until the sugar dissolves). Then add the milk into the warm butter and cocoa mixture and stir the mixture well.

3- Then combine the broken biscuits, walnuts, hazelnuts and the cocoa mixture in the bowl. To implement this process, turn it gently with a spoon. And maintain this process until all the broken biscuits, walnuts, hazelnuts come in contact with the cocoa mixture.

4- When the mixture has a thick consistency. Leave it to cool at room temperature.

5- Then pour the biscuit mixture on the cling film. Then spread it longitudinally over the cling film and wrap roll or pyramid shape. Then keep it in the freezer section of the refrigerator.

6- Refrigerate the mosaic cake for several hours or overnight before serving. When the cake is set, unwrap the cling film from one end and begin slicing it. Then close the cling film again and keep your cake in the refrigerator for several days.

7- Serve by slicing. Let stand for 5-10 minutes at room temperature before serving and sprinkle a pinch of nutmeg powder over the cake.

Enjoy!