Directions

1. In a small bowl, combine the mayonnaise, mustard, cumin, lemon juice, salt and pepper; cover and refrigerate until serving.
2. Grill green pepper, covered, over medium heat until skin blisters, about 6 minutes. With tongs, rotate pepper a quarter turn. Grill and rotate until all sides are blackened. Immediately place pepper in a bowl; cover and let stand for 15-20 minutes.
3. Meanwhile, shape beef into two patties. Grill, uncovered, over medium-hot heat for 7-9 minutes on each side or until a meat thermometer reads 160 degrees F.
4. Peel off and discard charred skin from green pepper; remove stem and seeds. Cut pepper in half. Top each patty with green pepper and cheese; grill 1 minute longer or until cheese is melted.
5. Grill buns, cut side down, for 1-2 minutes or until toasted. Spread bun bottoms with mayonnaise mixture; top with burgers, tomato, onion and lettuce. Replace bun tops.