Yolks with sugar and melted the butter must be placed in a water bath and stir until the sugar is melted. The mixture should not become too hot, do not cross. Remove from heat and stir with a mixer for about 3 minutes, until its volume increased 3 times. Add the flour, almond flour, salt, vanilla and baking powder and if you want. And add the beaten egg whites to stiff and stir gently with a spatula or spoon. In greased with margarine shapes or paper forms to pour 2-3 tablespoons of the mixture. Add marzipan on top, cut into pieces. Bake in preheated oven at 160C for 15-20 minutes. From this dose go 14 muffins.