Santa Fe Frittata

Position broiler rack 4 in. from heat. Heat broiler. Wrap handle (if not heatproof) of large nonstick skillet with foil. Heat 2 tsp oil in skillet over medium-high heat. Add frozen vegetables and 1/2 tsp salt; sauté 1 minute. Reduce heat to medium. Pour Egg Beaters over vegetables. Cover and cook, lifting edges of frittata occasionally to let liquid run under, 8 minutes or until almost set. Sprinkle with cheese. Broil 1 to 2 minutes, just until cheese melts. Cut in wedges; serve with salsa if desired.