Preheat the oven to 350 degrees F (175 degrees C).

Gather all ingredients.

Wrap green bell peppers in aluminum foil, and place in a baking dish. Bake for 15 minutes in the preheated oven. Remove from the oven.

Cook turkey in a skillet over medium heat until evenly brown. Set aside. Heat oil in the skillet, and cook onion, mushrooms, zucchini, red bell pepper, yellow bell pepper, and spinach until tender. Return turkey to the skillet. Mix in tomatoes and tomato paste, and season with Italian seasoning, garlic powder, salt, and pepper. Stuff the green peppers with the skillet mixture.

Return peppers to the oven, and continue cooking for 15 minutes.

Serve hot and enjoy!