Prep the peppers: Core and dice 2 bell peppers into bite-sized pieces.
Slice the third pepper into thin strips for texture variety. Set aside.
Sauté aromatics: Heat oil in a large skillet over medium. Add onion and a pinch of salt.
Cook 3 to 4 minutes until softened. Stir in garlic and cook 30 seconds until fragrant.
Brown the protein: Add ground turkey (or your choice). Break it up with a spatula.
Cook until no longer pink, about 5 to 7 minutes. Sprinkle in smoked paprika, oregano, cumin, chili powder (if using), black pepper, and a light pinch of salt.
Add peppers and tomatoes: Stir in the diced and sliced peppers, canned diced tomatoes, and tomato sauce. If the mixture looks thick, add 1/4 to 1/2 cup broth or water.
Simmer to soften: Cover and cook over medium-low heat for 7 to 10 minutes, stirring once or twice, until peppers are tender but still bright.
Fold in the grains: Stir in cooked brown rice, quinoa, or cauliflower rice.
If using cauliflower rice, cook 2 to 3 more minutes to warm through and absorb flavors. Taste and adjust salt and spices.
Optional cheese melt: Sprinkle cheese over the top. Cover for 1 to 2 minutes until melted.
Add a squeeze of lemon or lime if you like a fresh pop.
Finish and serve: Scatter chopped parsley or cilantro. Serve hot directly from the skillet.