Place oil in medium oven-safe skillet and heat over medium heat until hot. Add broccoli and mushrooms. Cook and stir 3 to 5 minutes or until vegetables are crisp-tender.
Pour Egg Beaters mixture into skillet; cook 5 to 6 minutes, or until center is almost set, gently lifting edges and tilting skillet occasionally to allow uncooked Egg Beaters mixture to run underneath.
Sprinkle top with cheese; place under broiler 2 minutes or until lightly browned and slightly puffed.
Cut into four wedges; serve immediately.