Soy lecithin is often confused with regular soy, but they're actually two very different products. Regular soy is made from the hulled seeds "soybeans," while soy lecithin refers to a derivative of the soybean which has been processed and had the oil extracted from it. Soy lecithin is available in either powder or granular form and is often found as an emulsifier in food products like margarine and salad dressing. Because it's not allergenic like regular soy, it's also added to some chocolates and baked goods. If you're comparing them for use in cooking, however, you'll want to stick with regular soybeans - especially if you're looking for a plant-based protein source!