Creamy soup recipes like this one do not typically freeze well since the dairy can separate. If you do want to make the soup to freeze, I would recommend leaving out the flour and milk. When you are ready to eat the soup let it thaw in the fridge. Then heat over medium heat until it comes to a low simmer. Combine 1 tablespoon of cornstarch with the milk and whisk into the soup. Return to a simmer and cook for 3-4 minutes until slightly thickened.