1In 4-quart nonstick Dutch oven, cook beef and onion over medium-high heat, stirring occasionally, until beef is thoroughly cooked; drain. Return to Dutch oven. Add garlic; cook and stir 1 minute.
2Stir in remaining ingredients except sour cream and green onions. Heat to boiling. Reduce heat to low; cover and simmer 30 minutes, stirring occasionally, until slightly thickened. To serve, top individual servings with sour cream and green onions.