Shortcrust dough: quickly knead all the ingredients together in a farling, the dough is very sensitive to heat, so do not work it for a long time, otherwise it will become “brandy”, that is, it will lose the binding. Rest in the refrigerator for 3/4 hour.
Roll out shortcrust pastry to 3mm thickness, flatten to size of tart, line tart pan with it. Brush the inside edge of the mold with water, line with pastry. Connect edge and bottom (press smooth). Brush the outer edge of the cake with egg yolk, wrap a strip of paper about 7cm wide around the mold to prevent it from spilling. Cream hand-warm butter with powdered sugar and lemon zest. Add egg yolks, cottage cheese and cornstarch, mix well. Beat egg whites, granulated sugar and salt until firm, fold into cake mixture. Pour the mixture into the prepared cake pan and bake very carefully in the heated oven. The heat must not exceed 160 °C! After 40 minutes, cover with paper or aluminum foil and bake with the oven door closed. When cool, remove from the pan and sprinkle with powdered sugar.
Oven temperature: 160 °C Baking time: 70 min.