A method for making a low carbohydrate high protein puffed snack food product. Ingredients comprising soy isolate, soy concentrate, corn meal, and water are introduced into an extrudate. The ingredients are extruded through a die orifice at a high specific mechanical energy. The ingredient formula ranges have been determined that maximize volumetric expansion and the set operating conditions and keep texture, color, and flavor acceptable. The puffed snack is then dried and seasoned. There are minimal off-flavors in the product.