Put 4 quarts water on to boil in a 6-quart pot. When water is boiling, add pasta.
In hot skillet, add 2 tsp olive oil, then sauté onions, peppers, mushrooms and pepperoni until vegetables start to sweat. Add garlic, olives and chicken, stirring often. When chicken is white and onions are translucent, remove from heat (be careful not to overcook vegetables or everything will be too soft)
Drain pasta when done.
In large bowl add pasta, meat mixture, topped with grated mozzarella, covered with marinara and tossed lightly. Top with grated Romano or Parmesan to taste. Serve immediately.
Makes: 4 to 6