|Ground beef||6 Ounce|
|Ground pork||6 Ounce|
|Ground veal||6 Ounce|
|Plain dry bread crumbs||1⁄4 Cup (4 tbs)|
|Minced onion||3 Tablespoon|
|Ketchup||2 Tablespoon (Plus Additional Ketchup For Serving)|
|Worcestershire sauce||1 Tablespoon|
|Hamburger buns||4 , split|
In medium bowl, combine the ground meats, bread crumbs, onion, ketchup, Worcestershire sauce, egg yolk, salt, and pepper; shape into 4 patties, each 1/2 to 3/4-inch thick.
Season grill grates; preheat on HI for 5 minutes, then reduce to appropriate cook setting.
Cook patties 18 to 25 minutes, turning after half the cooking time.
Toast buns during the last 2 to 13 minutes of cooking time, if desired.
Serve on toasted buns with additional ketchup on the side.