In 5-quart Dutch oven, cook beef, onions, bell pepper and jalapeño chile over medium-high heat 5 to 7 minutes, stirring frequently, until beef is thoroughly cooked; drain. Add flour, taco seasoning mix and salt; cook and stir 2 minutes. Gradually stir in milk, scraping bottom of pan. Heat to boiling; cook and stir 2 to 3 minutes or until slightly thickened. Remove from heat; add Velveeta™ cheese and 2 cups of the Cheddar cheese; stir until melted. Stir in rice and green chiles.