Beat 3 eggs in your mixing bowl for a few minutes.
Add sweeteners and beat again.
Add your melted butter, espresso powder and vanilla. Mix together.
Mix together the almond flour, baking powder, and cocoa powder.
Slowly add the dry mixture to the egg mixture. Mix until combined.
Add the chocolate chips and nuts, if using. Mix until just combined. Pour into prepared 8x8 pan.
Bake at 350 degrees. Start checking after 18 minutes. You want them baked, not jiggly but not over baked. I suggest not baking longer than 25 minutes.
Allow to cool somewhat before slicing. Store covered in the fridge.