85 % lean , high quality ground beef, Worcestershire , black pepper , chopped green onion, chopped fresh jalapeno, chopped fresh basil, a little fresh garlic, all mixed in the meat. top with tillimook smoked cheddar, or smoked Gouda ,lettuce , tomato ,thin cut onion. my favorite. I will sometimes add pan seared panchetta and some of the grease to the ground beef before cooking on the grill.