HEAT 1 Tbsp. of the dressing in large skillet on medium-high heat. Add meat; cook 2 min., stirring constantly.

ADD peppers and onions; cook and stir 5 min. or until steak is cooked through and vegetables are crisp-tender. Stir in remaining 3 Tbsp. dressing.

PLACE 2 cups of the greens on each of four salad plates. Top evenly with the steak mixture and cheese just before serving.