Tadd's Chili

1 lb. lean ground beef
1 lg. onion, chopped
1 pkg. taco mix
1 (30 oz). can chili beans
1 (30 oz.) can dark red beans
Salt
Pepper
Garlic powder
Meat tenderizer

Brown ground beef and drain. Season to taste with salt, pepper, garlic powder and meat tenderizer. Add onion, taco mix, chili beans and dark red beans. Simmer for about 1 hour (the longer the better).