Saute onions, garlic, and peppers in a large pan in oil untill golden. Tranfer to crock pot. Using same pan with oil from onions, brown meat cubes. Drain fluid, place meat in crock pot with onion mix. Brown hamburger meat, drain, mix in chili powder, place in crock pot. Add tomato and kidney beans. Cook on high 20 minutes. Add remaining ingredients, saving only cornstarch. Cook on low and covered 2 hours. Add cornstarch then serve.