Preheat oven to 375 F.
Use baking spray to grease 12 muffin tins (in absence of baking spray, lightly spray with regular oil spray. Lightly coat tins with flour and add another layer of spray).
Combine the almond flour, flour, salt, and sugar in a bowl.
Mix egg whites into the flour mixture.
Brown butter by heating in a 10 inch pan. Stir constantly until milk solids become a deep golden brown.
Add butter to flour mixture and mix to combine.
Distribute batter between the muffin cuts. Should be about 30 grams per muffin. Optionally add some chocolate to each tin.
Bake for about 14 minutes until edges are brown and tops are golden.