How to make a meringue roll with blueberries and cream

• Start mixing the egg whites and slowly add sugar until all is incorporated.
  3 egg whites, 100 g sugar
• Increase the mixer speed and mix the egg whites until they are thick, white, and shiny.
• Add potato starch and vinegar and mix briefly.
  1 teaspoon potato starch, 1 teaspoon vinegar
• Line a baking pan approximately 23/38 cm with parchment paper.
• Transfer the meringue to the pan and smooth the surface.
• Using a small spoon, dollop Stovit blueberry jam onto the meringue.
  about 80 g Jam
• Gently swirl the top to create patterns.
• Bake the meringue at 160 degrees (top/bottom heat) for 20 minutes.
• Prepare another piece of parchment paper, place it on the counter, and sprinkle with powdered sugar.
• Remove the baked meringue, gently flip it upside down, and place it on the parchment paper with powdered sugar.
• Gently peel off the paper from the bottom (the baking paper).
• Leave the meringue to cool.
• Prepare the cream - add cold mascarpone cheese, cold heavy cream, and powdered sugar to a bowl.
  125 g mascarpone cheese, 150 ml heavy cream, 1 tablespoon powdered sugar
• Mix everything on high speed until the mixture is thick.
• Add blueberries and gently mix.
  about 150 g blueberries
• Spread the cream over the meringue.
• Carefully roll up the meringue along the longer side - use the parchment paper to help you.
• Wrap the roll in parchment paper and put it in the refrigerator to chill - for at least an hour.