Veggie Frittata With Asiago Cheese

1 1/2 tsp Olive oil
1 Medium red onion, chopped
1 Red bell pepper, coarsely chopped
1 Medium zucchini, chopped
2 cups Packed spinach leaves, torn into 1 inch pieces
3 Large eggs
6 large egg whites
1/2 tsp salt
1/4 tsp Ground black pepper
1 oz Asiago cheese
1 cup Chopped tomatoes
1 Tbs Chopped fresh basil

1. Preheat broiler. Heat olive oil in 10-inch-diameter nonstick skillet over medium-high heat. Add onion and bell pepper; sauté until golden, about 8 minutes. Add zucchini; sauté until tender, about 5 minutes. Add spinach; stir until wilted, about 1 minute. Season with salt and pepper.

2. Whisk eggs, egg whites, salt and pepper in medium bowl to blend. Pour egg mixture over hot vegetables in skillet; stir gently to combine. Reduce heat to medium-low. Cook without stirring until eggs are set on bottom, about 5 minutes.