This gluten free brownie recipe can be made with walnuts, chopped almonds or your other favorite nut to up the protein and good fat content.
Preheat oven to 350 degrees F.
Grease a 13 x 9 baking tray with butter.
Cream together butter and sugar until light and fluffy. Mix in eggs, cocoa, vanilla, baking powder and salt until well incorporated.
Stir in xanthan gum, potato starch, almond meal, sorghum flour, coconut flour and milk until it's just combined. Fold in walnuts.
Pour into prepared pan and bake for 45 - 55 minutes, or until an inserted toothpick comes out clean. Set to cool. Serve.