Turn stock pot on medium high. Melt butter. Add celery, onion, carrots. Cook down until onions are transluscent. Add basil and garlic-shallot puree. After 3 minutes, add potatoes and stir another 3 minutes.
Carefully pour in 6 cups chicken broth. Boil for 20 minutes, then stir in a roux made from 4 tablespoons flour and 4 tablespoons butter.
Wait a few minutes for the soup to thicken slightly. Add cream. Whisk and simmer for 20 minutes.
Slowly stir in cheese and melt it down. After cheese is melted, pour into bowls and season with salt and fresh cracked pepper.