The use of chicken sausage makes this recipe Zone favorable.
Preheat oven to 400°F. Heat the oil in large oven-proof sauté pan. Add onion and cook until translucent, about 4 minutes. Add sausage, green beans, zucchini, bell pepper, and mushrooms. Season with salt and pepper. Sauté until tender, about 5 minutes. Remove from pan and set aside in bowl. Whisk egg whites until slightly foamy. Add egg whites to pan over medium heat. Stir briskly with wooden spoon. Let cook over medium heat until bottom of egg whites set. Distribute vegetables evenly over partially cooked egg whites. Remove pan from heat and place in oven until eggs are set, about 5 to 7 minutes. Serve immediately. Serve blueberries and mandarin oranges for dessert.