How to make a base and asparagus version. Once you've made this simple base — essentially milk or broth thickened with a cooked potato — you can make almost any cream of vegetable soup by adding the vegetable to the simmering potato mixture. When to add the vegetable depends on the cooking time for that particular vegetable.
Basic Creamed Soup
3 tbsp unsalted butter
4 medium leeks, white parts only
1 large (12-oz.) Yukon Gold or Idaho potato, peeled and cut into 1"-thick slices
6 cups milk, chicken broth or a combination
1-2 cups chosen vegetable
1/4 to 1 cup heavy cream (optional)
Salt and freshly ground black pepper
Basic Creamed Soup
Step 1: Heat the butter in a 4-quart non-aluminum pot over medium heat. Add the leeks and cook, stirring, until they turn translucent, about 8 minutes. Add the potato, milk, vegetable of choice (if it's slow cooking, otherwise it should be added nearer the end of cooking) and bring to a gentle simmer. Simmer for about 20 minutes, or until the potato and vegetable have completely softened and are easy to crush against the side of the pot with the back of a fork.
Step 2: Most of the time, vegetable creamed soups are best when quickly puréed in a blender and then worked through a food mill or through a medium-mesh strainer with the back of a ladle. If the mixture is thicker than you like your soup, thin it with a little milk or broth before adding the cream.
Step 3: Heat the soup, add as much cream as you like, and season with salt and pepper.
Cream Of Asparagus Soup
Step 1: Trim 2 lb. of asparagus by cutting off and discarding 2" from the base of each spear. Cut off the asparagus tips and boil them for 3 minutes in boiling salted water. Drain in a colander, rinse with cold water, and reserve. Cut the remaining stalks into 1" pieces and reserve.
Step 2: Prepare the soup base, adding the cut-up asparagus stalks at the same time as the potato. Purée the soup in a blender and work it through a food mill or a medium-mesh strainer with the back of a ladle.
Step 3: Reheat the soup and add as much cream as you like. Thin if necessary with additional broth, milk, or water. Season with salt and pepper (preferably white). You can add the reserved asparagus tips directly to the soup or heat them at the last minute in a little water and arrange them on top of the soup.
See more recipes from James Peterson.
Reprinted with permission from James Peterson's Vegetables, Revised (2012 Ten Speed Press).