The document discusses building a healthier burger option by finding alternatives to the existing bun and cheese that have fewer calories, less fat, and fewer carbohydrates. It analyzes the nutrition of the current bun and cheese and proposed alternatives, finding the alternative bun has fewer calories and fat and the alternative cheese has fewer calories and fat. Combining these alternatives results in a new burger with fewer total calories, less total fat, and fewer total carbohydrates than the original best-selling burger.