Preheat the oven to 350°F and lightly grease a small baking dish.
Cut off tops of peppers and remove seeds and membranes. Blanch peppers in salted boiled water for 5 minutes; remove and drain.
In a skillet, saute onions in vegetable oil until translucent. Add garlic and cook until fragrant.
In a large bowl, combine ground beef, sauteed onions and garlic, Seasoned Tomato Sauce for Meatloaf, white rice, salt and pepper. Mix until just combined.
Stuff mixture into each of the peppers and place upright into the prepared baking dish. Pour small can of tomato sauce over the peppers.
Bake for 40 to 50 minutes or until cooked through. Exact cooking time will vary based on the size of the peppers.