1 Preheat your oven to 350F while you prepare your batter.
2 In a large bowl, whisk together all wet ingredients except for flax egg. Once smooth, slowly stir in flax egg with a spatula.
3 Sift dry ingredients into the bowl, and combine, using spatula. Fold in any desired mix-ins.
4 Line a square baking pan with parchment paper and pour batter in. Bake for about 15 minutes, rotate the baking pan (I find this helps for any uneven baking) and bake for another 15 minutes or so,or until surface is golden brown, and a toothpick comes out clean.
5 Remove from oven and allow to cool. They will continue to cook and firm up, making cutting into bars easier. Divide into 9-12 bars.