Spread the nut mixture on a baking sheet and roast them dry in the oven at 180°C for about 10 minutes, then let them cool. Beat the eggs with sugar until foamy. Add melted butter and vanilla essence. Then mix in flour with baking powder and salt. Incorporate into the liquid mixture. A stiff dough will form, into which we finally work in the roasted nut mixture. Divide the dough into two equal parts and shape each by hand into a log, which we place on a baking sheet lined with parchment paper. Bake at 200°C for about 15 minutes. Then remove the sheet with the dough logs from the oven and, using a sharp knife, cut them diagonally into 1 cm thick slices. Spread the individual pieces on the baking sheet and return to the oven for another 10 minutes. Let them cool on the baking sheet.