fish: you can cook this on the grill, broil in an oven or sear in a pan. many fish options are high in protein here are some to consider: cod: in a 3 oz serving there's 15 grams of protein, 1 gram of fat, and no carbohydrates. tilapia: in a 3 oz serving there's 21 grams of protein, 1 gram of fat and no carbohydrates.