Preheat your oven to 375°F (190°C).

Prepare the bell peppers by slicing the tops off and removing the seeds. If needed, trim the bottoms slightly.

Sauté the onion and garlic in a skillet over medium heat with olive oil until they're translucent and fragrant.

Add the ground turkey or lean beef to the skillet. Cook until browned, about 6-8 minutes.

Combine the cooked quinoa or rice, diced tomatoes, salt, and pepper with the meat mixture. Stir well.

Stuff each bell pepper generously with the filling mixture and place them upright in a baking dish.

Cover the dish with foil and bake for 30 minutes. Remove foil during the last 10 minutes.

Garnish with fresh herbs before serving.