Other than protein powder, here are some protein rich ingredients to add to your oatmeal: 1) Nut butters or seed butters 2) Whole nuts and seeds (flax seeds, chia seeds and hemp seeds are very rich in protein) 3) Collagen powder (if you don't need this recipe to be vegan) 4) Whey protein powder or Greek yogurt (if you don't need this recipe to be vegan)