Celery is a familiar sight in the refrigerator, a few ribs already removed for use in a salad or veggie tray and the rest slowly turning pale and rubbery. The vegetable's crisp texture and fresh flavor are widely appealing when raw, but expanding your horizons to include cooked celery creates a number of new options. It's useful both as a flavoring for other foods and as a featured ingredient itself.
The Supporting Player
One of the most common ways to use celery in cooking is as a background flavor in finished dishes. This is because, like onions, garlic, parsley and mushrooms, celery has the happy characteristic of enhancing other flavors. In French cookery it's part of a classic flavoring mixture with onions and carrots, called "mirepoix." Mirepoix is typically used to provide a base of flavor for stocks, and the soups and sauces made from them. American cooks often put the same three vegetables beneath a roast, enhancing the flavor of the resulting gravy. As a rule, you can enhance the flavor of most soups, sauces and stir-fries by adding a handful of minced or finely chopped celery. In fine sauces, strain out the celery -- and other aromatic vegetables -- before serving.
Celery as a Vegetable
Although it's seldom used in American cookery as a vegetable in its own right, celery often forms a side dish in European kitchens. Peel the strings from the back of each rib with a vegetable peeler, before cooking whole ribs or lengths of celery. This makes it easier to cut at the table, with your fork or knife. Simmer or braise the celery in your favorite broth, and serve it as a cooked vegetable alongside meats or poultry. Alternatively, arrange prepared stalks of celery beneath or beside your bird or your roast, where they'll absorb flavors as it cooks. Fill the celery stalks with grain- or meat-based stuffing to turn them into a full meal, and bake them in white or tomato sauce with a cheese and breadcrumb topping.
In a Bowl
Aside from celery's value as an ingredient in stocks and broths, it makes a fine soup itself. Peel the strings from each rib, then chop them coarsely and saute them gently in the bottom of your pot with some chopped onion. Once the onion is translucent, add chicken or vegetable broth and simmer it until the vegetables are tender. Puree the soup, then add a generous splash of heavy cream and thicken the soup to your taste. Add diced cooked chicken if you wish, or fresh herbs -- celery plays well with most fresh herbs -- or even fruits such as pears.
Don't Forget the Leaves
The tuft of leaves that crown each cluster of celery are something of an afterthought for many cooks, but they provide a winning ingredient in their own right. Mince them to add a subtle and delicate celery flavor to stuffings for poultry, pasta or stuffed vegetables, or stir them into a risotto at the last minute to freshen and brighten its flavor. Scatter chopped or torn leaves over bowls of cream soup or delicate brothy soups as a last-minute garnish, both for their flavor and their delicate green color. Celery leaves even make an effective -- if non-traditional -- substitute for cilantro in tacos and other Indian or Mexican foods, if you're serving cilantro-averse diners.