Q. How do you correct a creamy soup when it has become too watery? — Jessica, Cleveland
A. Watery cream soups can come from a couple of different reasons. One of them is that the thickener that was utilized (be it a fat and flour roux or a liquid and flour or corn starch slurry) was inadequate. By inadequate I mean that there was not enough starch to hold the liquids in the desired thickened suspension. The solution to this problem is to either utilize more of the roux or slurry, or to utilize a roux or slurry that contains more starch.
Another reason that cream soups can become watery is that the vegetables or other ingredients in the soup continue to emit moisture through the cooking process. Mushrooms and potatoes are prime examples of vegetables that continue to “weep,” or lose moisture as they cook further, especially from a raw state. A solution to this is to initially over-thicken the soup in anticipation of the additional moisture. In that way, when the additional moisture presents itself, the soup will essentially thin itself to the desired consistency.
Yet another reason cream soups can become watery is if they have been frozen. The freezing process seldom enhances the quality of foods, mostly because as foods freeze their moisture expands and damages the cells of the foods. Often soups and other food products that have been frozen and thawed will need to have a small amount of thickener added to help tighten them back up to the desired consistency.
I hope this helps! Happy cooking, Jessica!