Brown beef; drain and set aside. Saute onion, carrots, celery, basil, and parsley in 1 tbsp. butter for about 10 minutes. Add potatoes and beef, bring to a boil. Simmer 10 minutes or until potatoes are tender. In a small skillet, melt remaining butter. Add flour. Cook and stir for 2 minutes. Reduce heat. Add cheese, milk, salt, and pepper. Cook until cheese is melted. Remove from heat, stir in sour cream.