Preheat your oven to 375°F (190°C).

In a large skillet over medium heat, pour in 2 tablespoons of olive oil. Once heated, add the lean ground turkey and cook for 5-7 minutes, breaking it apart with a spatula. Season with salt, pepper, paprika, and thyme.

Add the diced onion and bell pepper to the skillet with the turkey. Cook for about 5 minutes until softened.

Stir in the fresh spinach or kale, cooking just until wilted, about 2 minutes.

In a large mixing bowl, combine the turkey and vegetable mixture with cubed sweet potatoes. Toss everything together gently.

Transfer the mixture into a greased baking dish. Top generously with cheddar and mozzarella cheese.

Bake for 25-30 minutes or until the cheese is golden brown.

Once done, let the casserole rest for about 5 minutes before serving.