1. Preheat oven to 400 degrees.
2. In a large stockpot, over high heat, bring 3 cups of water to a boil.
3. Slice bell pepper in half, lengthwise, remove ribs & seeds.
4. Place bell peppers in boiling water for about 5-8 minutes, until slightly tender.
5. Remove bell peppers from water and place open side down to drain excess water.
6. Bring skillet to medium heat, spray with cooking oil, add diced onions, mushrooms, & ground turkey.
7. Stir mixture frequently and cook until meat is slightly brown and is 165°F.
8. Add a dash of black pepper and garlic powder for more flavor, if you desire.
9. Remove from heat and set aside.
10. Place cut bell peppers, open side up, in a lightly greased baking dish & fill each pepper with meat mixture.
11. Place a slice of low fat provolone cheese on top of each bell pepper.
12. Bake for 15-20 minutes or until cheese is melted.