To completely dry the dishes start to whisk the egg whites, gradually adding sugar. Add vanilla and continue to beat until grains of sugar are melted. The mass becomes thick and viscous. Put a lot of portion of a pastry bag or spoon into oiled and floured piece of parchment. Bake at 120 (!!!)* approximately 60-90 minutes. Brownies should not be baked and dry!!!! If you increase the temperature, the cakes will begin to crack on top and Browning, but the inside will remain raw. Remove from oven and let slightly cool. Then remove from parchment. If this procedure is difficult, spray the parchment with the back side a little water. Butter cream I don't oil, if you like, you can do it.