Grind the biscuits in a blender until they turn into a fine powder.

In a mixer, beat the eggs with the powdered sugar at high speed for about 10 minutes, until the mixture becomes fluffy and creamy.

Gradually incorporate the butter into the egg mixture, followed by the cocoa powder, ground biscuits, cognac, vanilla extract, and finally, the chopped walnuts.

Knead the mixture with your hands until all the ingredients are combined. Divide it into 4 portions and shape each into a roll.

Wrap each roll tightly in plastic wrap, twisting the ends like candy to compress the shape. Place them in the freezer for 1 to 1.5 hours to firm up.

Once chilled, remove the plastic wrap and slice the rolls into 1 cm thick pieces using a sharp knife.

Dip each slice into the melted chocolate, ensuring it’s fully coated. Use two forks to flip and remove the pieces. Place them on parchment paper to cool and allow the chocolate to set.

Once the chocolate has hardened, store the chocolate-walnut rolls in the refrigerator.