Navy bean soup is a hearty, savory soup with just a hint of sweetness. Most recipes, however, come out a little watery. If you want to thicken your navy bean soup, there are several techniques that will do so while adding to the flavor of your dish. You can thicken your bean soup with roux, potatoes, flour, cornstarch or mashed beans from the soup itself.
Things You'll Need
Navy bean soup
1 cup flour
1 cup roux
1 lb. unsalted butter
Wash and peel potatoes. You can use any type of potato you wish, but the flavor of yellow potatoes go best with the soup.
Boil potatoes. You want the potato to soften, but not become so waterlogged that it starts to disintegrate. Seven to ten minutes on high heat should soften the potato enough to mash.
Mash or puree potatoes. You can use a potato-mashing tool or a fork. To puree the potatoes, simply run them through a food processor or blender.
Stir potatoes into navy bean soup. You can add the potatoes either during the final stages of cooking the soup or later on during reheating.
Make clarified butter. Clarified butter is unsalted butter from which milk solids and whey proteins have been filtered. To make clarified butter, heat unsalted butter in a saucepan over low heat. After about five minutes, the whey proteins will float to the top in the form of a white froth and the milk solids will sink to the bottom. Use a spoon to skim off the froth on top. Then pour the rest of the butter through a cheesecloth. The clarified butter will strain out the milk solids leaving you only the clarified butter.
If you store clarified butter in an airtight glass jar, it will keep for up to a year. Buy a couple pounds of your favorite butter when it is on sale and make clarified butter to keep on hand for future recipes.
Heat clarified butter. If you are using pre-made clarified butter that was stored in the refrigerator, heat it under low heat on the stove.
Mix clarified butter and flour. When making roux, always mix equal parts of flour and fat, in this case clarified butter. Use a whisk and stir the flour in slowly to ensure a smooth texture.
Heat roux mixture. Once flour and clarified butter are smoothly mixed, heat the roux over low heat, stirring frequently. Roux is very delicate and it must be monitored closely.
There are four types of roux: white, blond, brown and dark brown. The longer you cook the roux, the darker it gets. White and blond roux are used for thickening soups. After five minutes you will have white roux. After 20 minutes, you will have blond roux.
Mix into navy bean soup. It is best to add the roux during the final stages of cooking the navy bean soup.
Rinse navy beans. Since this soup is a bean soup, it is best to use the same beans called for in the recipe.
Soak beans. It is best to let beans soak overnight, but they should at least soak for eight to ten hours.
Cook beans. You can cook more beans in the soup than the recipe calls for, knowing that you will mash them up in the soup as a thickening agent. Another alternative is to cook and mash the extra navy beans separately, then add them to the soup during the final cooking stages.