- Whip the eggs at room temperature with sugar until fluffy.
- Sift the flour, cocoa and baking powder, and carefully add to the egg mixture, mixing at a slow speed for no more than 30 seconds. Tthen with a spatula from top to bottom.
- Spread the batter on parchment, over the entire baking sheet.
- Bake it at 338F (170C) for 15 minutes.
- Take the biscuit out of the oven, roll up, and wrap in a damp towel. Cool it like this.
- Put frozen berries in a saucepan, and add sugar.
- Boil over medium heat, stirring until the mass boils and thickens.
- At the end add starch, and stir until dissolved.
- Cool the confit.
- Whip the mascarpone (or cream cheese) with powdered sugar until fluffy.
- Add cold cream, and whip for another minute.
Heat the water with sugar in a saucepan until the sugar dissolves, and cool it.
Unfold the biscuit, and soak it.
Spread the cream on the cooled biscuit, and then the berry filling.
Carefully twist it into a roll.
- Melt the ingredients in the microwave or in a water bath.
- Mix well, and brush the roll with a brush.