Mix the flour, cocoa, baking powder and salt together. Beat the eggs with the stevia until frothy. Stir the dry ingredients into the eggs and then mix with the applesauce. Put the dough in an oblong silicone baking pan.
Bake in the preheated oven for about 20-25 minutes.
Let the cake cool in the baking pan for about 15-20 minutes and then place it on a rack to cool completely.