Place oats in food-safe plastic bag. Seal bag securely, squeezing out excess air. Roll over bag with rolling pin to crush oats to a fine consistency.
Combine Ground Beef, oats, and steak seasoning blend in large bowl, mixing lightly but thoroughly. Lightly shape into four 1/2-inch 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.
Line bottom of each bun with lettuce and tomato, if desired; top with burger and cheese slice. Close sandwiches.
Nutrition information per serving: 450 Calories; 126 kcal Calories from fat; 14 g Total Fat; 6 g Saturated Fat; 4 g Monounsaturated Fat; 82 mg Cholesterol; 745 mg Sodium; 41 g Total Carbohydrate; 1.2 g Dietary Fiber; 37 g Protein; 4.4 mg Iron; 9 mg NE Niacin; 0.4 mg Vitamin B6; 2.4 mcg Vitamin B12; 6.4 mg Zinc; 22.1 mcg Selenium; 83 mg Choline;