PUREED VEGETABLE SOUPS

INITIALLY, WE SET OUT TO DEVELOP A SINGLE master recipe for pureed vegetable soup, hoping that the same technique could be used with all vegetables. We quickly discovered that green vegetables, such as peas and asparagus, must be handled differently from the heartier, more starchy vegetables, such as carrots and butternut squash.

Dense winter vegetables are bulky enough to act as their own thickener. There is no need to add flour or cream to thicken soups made from these vegetables. Green vegetables, however, are not starchy enough to use on their own. They require flour and cream. Loss of color is another issue when making soups made from green vegetables. The two types of pureed soup are considered separately in this chapter.

SOUPS WITH HEARTY VEGETABLES

We enjoy the smooth, silky texture of creamed vegetable soups, but we often find the flavor to be lacking. The dairy elements (usually lots of butter and cream) mask the taste of the vegetables. Instead of an intense carrot flavor in a creamy base, for example, we usually taste cream with carrots in the background.

We wanted to see if there was a way to make a pureed soup that tasted more like vegetables. We wanted a creamy carrot soup reminiscent of the sweetest carrots, a butternut squash soup that really had the flavor of squash. And we were not willing to sacrifice anything in terms of consistency. Puréed vegetable soups must be silky. Otherwise, there is no point in pureeing them.

Most creamy vegetable soups contain flour. While we find flour to be essential when working with more watery green vegetables, starchy vegetables don't seem to need flour. In fact, when flour is added to soups made with dense, starchy vegetables, the texture becomes overly thick and starchy.

To find our way, we decided to use carrots as a model and then test other vegetables after developing a basic recipe. We started out by experimenting with other starches (cornstarch and potato starch) but found the results to be similar to soups made with flour. The texture was still too thick and gummy, and the vegetables were not the primary flavor. We had also seen recipes using potatoes or rice as thickeners, usually cooked right along with the vegetables in broth. When we tried this, though, the potatoes and rice detracted from the carrot flavor and caused the color of the soup to fade.

We found that the elimination of the starch improved the texture of the soup, but the recipe we were working with had a dairy component, and its flavor still dominated. It seemed to us that the best idea might be to use a larger quantity of vegetables and puree them for texture.

Most recipes for pureed vegetable soup use equal amounts of vegetables and liquid, or in some cases slightly more liquid than vegetables. We decided to alter this ratio in a big way and cook four cups of carrots in two cups of stock. We figured we would get more vegetable flavor and could use the vegetables themselves as a thickener.

This change resulted in an immediate improvement. By the time the vegetables were cooked, the mixture was thick enough to create a puree with good body. In fact, the pureed carrots and broth were actually a little too thick. Instead of adding cream to the vegetables as they cooked, we now needed to add cream to the blender to thin out the pureed carrots.

We used about one cup of cream to get the right consistency, but this was too much dairy fat for our taste. Next, we tried substituting half-and-half as well as whole and low-fat milk. We found that whole milk provided just the right amount of dairy fat to improve the texture, providing smoothness and a creamy mouthfeel without overwhelming the carrot flavor. Adding skim milk or 2 percent milk was like adding more broth—not at all satisfying. Half-and-half was good, but a tad too rich.

Now that we had successfully developed a bright orange carrot soup that tasted of good, sweet carrots, we wondered what other vegetables might take to this technique. Watery vegetables refused to work. Mushrooms, for instance, don't have enough fiber and bulk to work as their own thickening agent. Peas and asparagus are also poor candidates for this technique, which works best with tubers, roots, and hearty winter vegetables.

We have included recipes using carrots, butternut squash, and cauliflower, but the same technique can be applied to parsnips, turnips, beets, or sweet potatoes. These soups also taste delicious cold. To serve them cold, start off with oil instead of butter; unlike butter, the oil won't congeal when chilled.