The butter is melted and added sugar. To the resulting mixture add the sifted flour, hazelnuts, egg, lemon peel and baking powder. It was stirred and kneaded to give a homogeneous paste. Put it in the refrigerator for about 1 hour. Attention is about 2/3 of the dough and roll it to a thickness 1.5 cm. The resulting crust smeared with jam. The remaining 1/3 of the dough is rolled out and cut into strips. The strips are arranged in a certain distance on covered with jam dough so as to obtain a diamond lattice. This grid is coated on top with beaten egg. Bake about 40 minutes in the preheated oven to 200 ° C.