I can remember my grandmother making oyster stew when I was very young. Though I certainly did not share her enthusiasm for oysters then, I now enjoy them very much. If you would prefer to make a clam chowder, you can easily substitute clams for the oysters. I chose to use the clam base concentrate because it nicely complemented the flavor of the oysters. It is also a stocked item at my grocery store and can be found near the canned broth options.
It is very simple to thin a soup—simply add more liquid. If, however, you need to thicken your soup, you can do so by simmering longer without the lid; evaporation eventually will take care of it. For much faster results, try adding a thickening agent like flour, cornstarch, or dried potato flakes. When adding a thickener to the soup, do not add it directly—first remove a little liquid from the soup and in a small bowl create a thick paste; then add that back to the soup, stirring gradually, and then allow that to cook for a few minutes to make certain the dry, floury flavor is cooked out.