Roulade 'birch”

Roulade 'birch”
Cake: 8 jaj, 8 spoons of sugar, 8 tablespoons of flour, <9 /yże / r potato flour, grease to lubricate the mold
White icing: 20 day of sugar, a quarter of a glass of water, the juice of half a lemon or half a teaspoon of vinegar (3 %)
Black icing: 25 day of sugar, half a glass of water, spoon of vinegar (3%), 10 a dag of grated chocolate, 2 a dag of cocoa or plain butter

Beat egg yolks with sugar, add flour, potato flour and beaten to a stiff protein foam. Mix carefully, Pour onto a greased baking tray and put into the oven immediately. Baking time approx. 30 min. Cool the baked cake slightly and use a sharp knife to cut it into two slices. Sprinkle with sweetened water with the addition of rum or arrack, spread with cake mass or blueberry jam and roll. Place one rolled slice in a springform pan, form the side ones from the other, smaller branches and glue on the sides and top. Top with white icing, make transverse stripes from the dark - like on a birch trunk. Preparation of white and black icing: Pour the water into the enamel saucepan, add sugar, cover and cook, until it thickens enough, that a drop in cold water will not dissolve. When the syrup is the right thickness, add half of the vinegar or lemon juice and place the dish in very cold water, to let the contents cool down rapidly. Twist with a wooden rolling pin or a spoon, until the frosting is completely white, then add the rest of the vinegar or lemon. Proceed in the same way when making black icing, and when it becomes white, add chocolate, melted cocoa butter or plain butter.