Warm the pan. Heat a large skillet over medium heat.
Add the olive oil and swirl to coat.
Soften the aromatics. Add the diced onion and bell pepper. Cook 3–4 minutes until softened. Stir in the minced garlic and cook 30 seconds until fragrant.
Brown the turkey. Add the ground turkey, breaking it up with a spatula.
Season with 1 teaspoon salt and a few cracks of black pepper. Cook 5–7 minutes until no longer pink and lightly browned.
Spice it up. Sprinkle in smoked paprika, oregano, cumin, and red pepper flakes. Stir to coat the turkey and vegetables so the spices bloom in the heat.
Build a light sauce. Stir in tomato paste, then pour in the chicken broth.
Scrape the bottom of the pan to release any browned bits. Simmer 2–3 minutes to slightly thicken.
Wilt the spinach. Add the spinach in batches, tossing as it wilts. Keep adding until all the spinach is just wilted but still bright green, about 2–3 minutes.
Brighten the flavors. Turn off the heat.
Add the zest of half the lemon and 1–2 teaspoons lemon juice. Taste and adjust salt, pepper, and lemon as needed.
Finish and serve. Top with feta or Parmesan and a sprinkle of parsley, if using. Serve on its own, or spoon over brown rice, quinoa, cauliflower rice, or whole-grain pasta.