Ingredients

• 2 Tbsp. extra-virgin olive oil, plus more for drizzling
• 1 medium yellow onion, chopped
• 3 cloves garlic, finely chopped
• 2 Tbsp. tomato paste
• 1 lb. ground beef
• 1 1/2 cups cooked white or brown rice
• 1 (14.5-oz.) can diced tomatoes
• 1 1/2 tsp. dried oregano
• Kosher salt
• Freshly ground black pepper
• 6 bell peppers, tops and cores removed
• 1 cup shredded Monterey Jack cheese
• Chopped fresh parsley, for serving

Instructions 

1. Place a rack in the center of the oven and preheat to 400°. Heat the olive oil in a large skillet over medium heat. Add the chopped onion and cook, stirring occasionally, until soft and translucent, about 7 minutes. Stir in the garlic and tomato paste and cook for about 1 minute, until fragrant.
2. Add the ground beef to the skillet. Cook, breaking it apart with a spoon, until it is no longer pink, about 6 minutes.
3. Stir in the cooked rice and diced tomatoes. Season with oregano, salt, and black pepper. Let the mixture simmer, stirring occasionally, until some of the liquid cooks off, about 5 minutes.
4. Arrange the hollowed bell peppers upright in a 13" x 9" baking dish. Lightly drizzle the peppers with olive oil. Spoon the beef mixture evenly into each pepper. Cover the baking dish tightly with foil.
5. Bake until the peppers are tender, about 35 minutes. Remove the foil, sprinkle the peppers with shredded Monterey Jack, and return to the oven. Continue baking until the cheese is melted and bubbly, about 10 minutes more.
6. Finish with chopped parsley just before serving.

• Pepper texture: Leaving the peppers raw before baking keeps them sturdy enough to hold the filling while still becoming tender in the oven.
• Make-ahead option: The filling and peppers can be prepared separately a day in advance and stored in airtight containers in the refrigerator until ready to assemble and bake.
• Freezing: The stuffed, unbaked peppers can be frozen for up to 3 months. Bake from thawed or frozen, adding extra time as needed.