Preheat oven to 350. In a large skillet, brown turkey until all liquid is evaporated. Season with salt.
Add onion, cilantro, garlic, taco seasoning, beans and tomatoes. Mix together well and cover, simmer on low for 20 minutes.
Stir in frozen corn, recover and simmer for about 5 minutes, till excess liquid is gone.
While turkey mixture is simmering, cut peppers lengthwise and remove the stem and all seeds, rinse off and pat dry if necessary.
Lay peppers open side up in a dish, pour chicken broth into the bottom of the dish.
Fill each pepper with turkey mixture till full. Cover the dish with foil and bake for 50 or so minutes, till peppers are tender.
Take dish out and carefully remove foil, there will be steam.Top each pepper with Mozzarella and chili powder.
Return to oven, uncovered and bake until cheese is melted, about 3-5 minutes.