Fumet is a white stock made from fish bones and aromatic vegetables, which are first “sweated” (cooked until soft but not taking on any color), then simmered in water. That initial step is a crucial building block, eliciting a touch of sweetness from the leek and developing the flavors for the next step, though it will produce a stock with less clarity than when the aromatics are simply brought to a boil with the rest. (To achieve that result, follow recipe for Basic Chicken Stock on page 41, bringing the fish bones and heads to a boil, then adding vegetables, bay leaf, and peppercorns and simmering 30 minutes before straining.) With its concentrated flavor, fumet is ideal for making fish soups and stews, or for steaming shellfish, such as the Clams in Herbed Broth on page 219. Like other stocks, fumet can be altered for different effects. Increase the ratio of bones to water and you will have a stock with more pronounced fish flavor. For a Mediterranean-style stock, chopped garlic and fennel (and its fronds) can be sweated with the other aromatics, then crushed tomatoes, crumbled saffron, and a few parsley stems added and simmered in the pot along with everything else.

　　

Ingredients

Makes about 2 quarts

　　2 tablespoons sunflower or other neutral-tasting oil

　　2 pounds fish bones and heads

　　1 celery stalk, cut into 1-inch pieces

　　1 leek, white and pale green parts only, cut into 1-inch half-moons and washed well (page 32)

　　1 cup dry white wine

　　1 dried bay leaf

　　5 whole black peppercorns

　　

Step 1

Sweat the bones and vegetables Heat the oil in a medium stockpot over medium heat until hot but not smoking. Add fish parts, celery, and leek. Cover and cook, stirring once or twice, until vegetables are soft and translucent and flesh on the bones has turned opaque but not brown, about 3 minutes.

　　

Step 2

Make stock Add wine and reduce by half, 3 to 5 minutes, then add enough water to cover by 1/2 inch (about 2 quarts) along with the bay leaf and peppercorns. Bring to just under a boil over medium-high heat, skimming foam with a ladle as it rises to the surface, then reduce heat and gently simmer (bubbles should just gently break the surface) for 35 minutes, skimming frequently.

　　

Step 3

Strain stock Pass mixture through a fine sieve into a heatproof bowl or another pot (do not press on solids), discarding solids. Skim off fat. If not using immediately, let cool completely (in an ice-water bath, if desired) before transferring to airtight containers. Fish fumet can be refrigerated in airtight containers for up to 2 days or frozen for up to 3 months; thaw completely in the refrigerator before using.

　　

Ingredients

Step 4

Ask your fishmonger to save the bones and heads from the fish in advance; firm-fleshed white fish, such as snapper, bass, and halibut, work best. Avoid oily fish (such as mackerel and tuna).

　　Reprinted with permission from Martha Stewart's Cooking School: Lessons and Recipes for the Home Cook by Martha Stewart. Copyright © 2008 by Martha Stewart. Published by Crown Publishing. All Rights Reserved.Martha Stewart is the author of dozens of bestselling books on cooking, entertaining, gardening, weddings, and decorating. She is the host of The Martha Stewart Show, the Emmy-winning, daily national syndicated program, and founder of Martha Stewart Living Omnimedia, which publishes several magazines, including Martha Stewart Living; produces Martha Stewart Living Radio, channel 112 on SIRIUS Satellite Radio; and provides a wealth of ideas and information on www.marthastewart.com.