Form meat into 4 1/2-inch-thick patties; sprinkle with seasoning.
Grill burgers over direct high heat for 5-6 minutes on each side or until 160°F for medium doneness.
Meanwhile, place onions in disposable foil pan sprayed with cooking spray. Grill 5-7 minutes or until vegetables are crisp-tender, turning occasionally. Remove from grill.
Top burgers with cheese. Place rolls, cut sides down, on grill. Cook 1 minute or until cheese is melted and buns are lightly toasted.
Place cheeseburgers on buns, and top with lettuce, onions and tomatoes.
Tips
When you’re grilling up burgers, don’t forget the Weber® Gourmet Burger™ Seasoning.