FEWER THAN 10 INGREDIENTS / FAST/SLOW / NATURAL RELEASE / GLUTEN-FREE / FREEZES WELL
Fish Stock
Makes 10 cups
If you want to get serious about making stock and wanted to know the one stock to make, we would say, “This one.” Odd, no? But there are pretty decent versions of vegetable and chicken broth on the market. Fish broth is another matter. And there’s no substitute for a fine fish stock in just about any fish soup, stew, or braise. Some people try to jury-rig a fish stock by adding bottled clam juice to canned chicken or vegetable broth. It’s a pale imitation. If you really want to become a pro, make your own fish stock and mix it in about 50/50 proportions with purchased chicken or vegetable broth for any fish recipe in this book. Where do you get fish heads and such? Walk up to the fish counter of any large supermarket. Ask and you might receive.
3 pounds fish heads, tails, fins, skin, and bones, preferably with a little meat still adhering to them
4 medium carrots, cut into 2-inch pieces
4 medium celery stalks including any leaves, cut into 2-inch pieces
1 medium yellow onion, peeled and halved
1 tablespoon black peppercorns
1 teaspoon kosher salt
10 fresh parsley sprigs
2 bay leaves
At most 2½ quarts (10 cups) water
1. Put the fish parts, carrots, celery, onion, peppercorns, salt, and parsley sprigs in a 6- or 8-quart cooker. Pour in as much water as possible without going over the Max Fill line. Lock the lid onto the pot.
2.
Set the machine for: SOUP / BROTH and NUTRIBOOST
Set the level for: MAX
The valve must be: 
Set the time for: 35 minutes with the KEEP WARM setting off
If necessary, press: START
Set the machine for: SOUP / BROTH, PRESSURE COOK, or MANUAL
Set the level for: HIGH
The valve must be: Closed
Set the time for: 45 minutes with the KEEP WARM setting off
If necessary, press: START
Set the machine for: SLOW COOK
Set the level for: HIGH
The valve must be: Opened
Set the time for: 4 hours with the KEEP WARM setting off (or on for no more than 2 hours)
If necessary, press: START
3. If you’ve used a pressure setting, when the machine has finished cooking, turn it off and let its pressure return to normal naturally, about 40 minutes.
4. Unlatch the lid and open the cooker. Strain the contents of the insert through a fine-mesh sieve like a chinois (or through a colander lined with a double thickness of cheesecloth) and into a large bowl. Cool for 30 minutes, then skim any impurities off the surface of the stock. Store in covered containers in the fridge for up to 2 days, or in 1-cup covered containers in the freezer for up to 4 months.