Preheat oven to 400°. In a small saucepan, put together rice in accordance with package deal directions. In a big skillet over medium warmth, warmth oil. Prepare dinner onion till delicate, about 5 minutes. Stir in tomato paste and garlic and prepare dinner till aromatic, about 1 minute extra. Add floor beef and prepare dinner, breaking apart meat with a wood spoon, till not pink, 6 minutes. Drain fats.
Return beef combination to skillet, then stir in cooked rice and diced tomatoes. Season with oregano, salt, and pepper. Let simmer till liquid has diminished barely, about 5 minutes.
Place peppers minimize side-up in a 9″-x-13″ baking dish and drizzle with oil. Spoon beef combination into every pepper and prime with Monterey jack, then cowl baking dish with foil.
Bake till peppers are tender, about 35 minutes. Uncover and bake till cheese is bubbly, 10 minutes extra.
Garnish with parsley earlier than serving.
