Brown the ground beef and onions in a large skillet; drain the excess fat, then transfer the browned beef and onions to a large slow cooker or a stockpot. Add the beans, corn, tomatoes, green chiles, black olives, green olives, taco seasoning, and ranch dressing mix, and cook in a slow cooker on low for 6 to 8 hours or simmer over low heat for about 1 hour in a pot on the stove. To serve, place a few corn chips in each bowl and ladle soup over them. Top with sour cream, cheese, green onions and jalapenos.