It is well established in scientific literature that cooked meat and fish produce carcinogenic heterocyclic amines (HCA) which are derived from creatine found in muscle tissue. Our research and peer-reviewed literature suggests HCA can be derived from arginine, found in proteinaceous plants, rather than creatine. We have conducted cooking experiments with arginine and phenylalanine, performed a series of separations, and have isolated three new HCA candidates. These compounds are being characterized for their chemical structure and toxicity but their low yields present challenges. This new class of carcinogens will aid in assessing risks with the cooking of protein-rich plant products.