Pro Tips: For the deepest flavor, sauté the onions and peppers until very soft before adding the garlic. Use lean ground beef (85%-90%) to avoid a greasy filling without sacrificing tenderness. The simmering time is key for the sauce to thicken and the flavors to marry—don't rush it! Toast your buns to prevent sogginess and add great texture. For a richer sauce, stir in 1-2 tablespoons of tomato paste with the garlic.