Place the sweet potatoes in a large saucepan with just enough water to cover. Bring to a boil and cook until the potatoes are tender. About 12 minutes.
Drain and mash, then season with salt, pepper, sour cream, butter and Italian seasoning blend.
While sweet potatoes are boiling, heat oil in a large nonstick pan over medium-high heat. Sauté the onions for 3-4 minutes, then stir in the garlic and cook for a minute or so.
Add the ground turkey and cook, crumbling with a wooden spoon, until the meat is cooked through and liquid is absorbed. About 20 minutes.
Stir in the tomato paste, oregano, smoked paprika, salt, pepper, and chicken broth. Simmer for a few minutes until the liquid is reduced, then stir in the peas and corn.
Preheat the oven to 375°F.
Spread the turkey mixture into a 3-quart casserole dish or rectangle baking dish. Add mashed sweet potatoes on top and spread it evenly all the way to the sides.
Bake until the potatoes are just starting to brown, about 30 minutes. Rest, then serve.