01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish with cooking spray or a small amount of oil.
02 - Heat 1 tablespoon olive oil in a large skillet over medium heat. Add ground turkey and cook until browned and cooked through, breaking up with a spatula, about 5-6 minutes. Remove turkey from skillet and set aside.
03 - In the same skillet, add remaining olive oil. Sauté onion for 2-3 minutes until softened. Add garlic and red bell pepper, cooking for another 2 minutes until fragrant.
04 - Stir in diced sweet potatoes, thyme, oregano, smoked paprika, salt, and pepper. Cook, stirring occasionally, for 5 minutes to begin softening the potatoes.
05 - Add spinach and cooked turkey back to the skillet. Mix well and cook until spinach is just wilted, about 1-2 minutes.
06 - Transfer mixture to the prepared baking dish. Pour chicken broth evenly over the mixture.
07 - Sprinkle mozzarella and Parmesan cheese evenly on top of the mixture.
08 - Cover with aluminum foil and bake for 30 minutes to allow sweet potatoes to cook through.
09 - Remove foil and bake an additional 10-15 minutes, or until sweet potatoes are tender when pierced with a fork and cheese is golden brown and bubbly.
10 - Let casserole cool for 5 minutes before serving to allow flavors to meld and make serving easier.