Preheat oven to 375°F (190°C). Grease casserole dish.
In a skillet, heat oil and sauté onion, garlic, and bell pepper until softened.
Add ground turkey, season with paprika, oregano, salt, and pepper. Cook until browned.
Meanwhile, boil sweet potatoes until fork-tender, then mash with milk, olive oil, and a pinch of salt.
Layer cooked turkey mixture into the casserole dish, top with spinach, then spread sweet potato mash evenly on top.
Garnish with cheese & bake for atleat 20-25 minutes, until you get the light golden & bubbly texture.
Let rest 5 minutes before serving.