Combine Ground Beef and steak seasoning in large bowl, mixing lightly but thoroughly. Lightly shape into four 1/2-inch thick patties.
Place patties on grid over medium, ash-covered coals. Grill, covered, 8 to 10 minutes (over medium heat on preheated gas grill, 7 to 9 minutes) until instant-read thermometer inserted horizontally into center registers 160°F, turning occasionally. About 2 minutes before burgers are done, place buns, cut sides down, on grid. Grill until lightly toasted. During last minute of grilling, top each burger with cheese slice.
Line bottom of each bun with lettuce; top with tomato, burger and toppings, as desired. Close sandwiches.
Nutrition information per serving: 337 Calories; 110.7 kcal Calories from fat; 12.3 g Total Fat; 5 g Saturated Fat; 0.1 g Trans Fat; 1.3 g Polyunsaturated Fat; 4.2 g Monounsaturated Fat; 91 mg Cholesterol; 609 mg Sodium; 24 g Total Carbohydrate; 1.1 g Dietary Fiber; 4.3 g Total Sugars; 32.3 g Protein; 0 g Added Sugars; 140 mg Calcium; 4.8 mg Iron; 581 mg Potassium; 0.1 mcg Vitamin D; 0.4 mg Riboflavin; 8.3 mg NE Niacin; 0.5 mg Vitamin B6; 2.9 mcg Vitamin B12; 314 mg Phosphorus; 7.1 mg Zinc; 35 mcg Selenium; 107 mg Choline;