1 cup finely shredded 6 Cheese Italian Blend, divided
Preheat oven to 375°F. Line a large rimmed baking sheet with parchment. Slice the peppers in half lengthwise and remove seeds. Place peppers cut-sides down on baking sheet and drizzle with 1 tbsp oil. Bake 15 min., or until tender.
Meanwhile, in a 12-inch nonstick skillet, heat remaining 1 tbsp oil on medium-high. Add the ground beef and onion. Season with salt and pepper. Sauté until beef is almost fully cooked, 6–8 min., stirring and breaking up beef with back of spoon.
Microwave the rice according to package directions. To skillet, add rice, tomato sauce, and ½ cup cheese. Stir to combine and cook 2–3 min., until mixture is warm. Remove from heat
Carefully remove baking sheet from oven and flip peppers so they are cut-sides up. Spoon beef and rice mixture into each pepper. Top filled peppers with remaining ½ cup cheese. Bake for about 5 min., or until cheese has melted.