- Preheat the oven to 350 degrees F. Cut bell peppers in half; remove stems, membranes and seeds. If using, mix sauce ingredients in a small bowl and set aside. Place bell peppers on a plate and cover with plastic wrap. Microwave on high for approximately 3 minutes or until just tender. You may have to do this in a couple of batches. If you don't have a microwave, place peppers in a large pot of boiling water and parboil them until just tender, 2 to 3 minutes. Remove with a slotted spoon and dry on paper towels.
- In a large saut pan or skillet, heat the olive oil over medium-high heat. Add the diced onions and minced garlic and saut, stirring, until soft, about 3 minutes. With a slotted spoon, remove and place in large mixing bowl. Add the rest of the ingredients and mix well. Drizzle remaining olive oil (used to cook onions and garlic) inside the peppers. Stuff the bell peppers with the meat mixture. Note: I like to really stuff the bell peppers with lots of the meat mixture. If using, top with sauce mixture. Place in a 9x13-inch baking dish.
- Add 1/4 cup water, chicken or beef broth to bottom of pan. Bake for approximately 60 minutes or until the internal temperature is 150 to 160 degrees F. Remove from the oven and let rest for 10 minutes before serving.