Brown the ground beef. Drain and set aside.
In same large saucepan, melt 1 T butter over medium heat. Sauté onion, carrots, celery, basil and parsley until veggies are tender, about 10 minutes.
Add potatoes, ground beef and broth; bring to boil. Reduce heat; simmer , covered until potatoes are tender, 10-12 minutes.
Meanwhile in small skillet, melt remaining butter. Add flour, cook and stir until bubbly, 3-5 minutes. Add to soup; bring to boil. Cook and stir 2 minutes.
Reduce heat to low. Stir in cheese, milk salt and pepper; cook until cheese melts. Remove from heat; blend in sour cream.