Preheat oven to 350 degrees Fahrenheit. Line a long baking sheet with Gefen Parchment Paper.

In the bowl of an electric mixer, beat the egg whites with one cup of sugar. Set aside.

Beat the egg yolks with the oil, remaining two cups of sugar, potato starch, walnuts, vanilla sugar, and dissolved coffee. Fold the mixture into the egg whites and mix very well.

Pour batter onto the baking sheet and bake for 45 minutes.

When cool, cut into bars or use a cookie cutter to create fun or elegant shapes. Drizzle with melted chocolate.