Episode 122: Good Catch! 
Recipe: Baked Mackerel With Potatoes And Onions (Mackerel with Potatoes, Onions, and Tomatoes)
Fresh mackerel is nutty, fleshy, and moist — but it has to be fresh to be good. It’s excellent broiled to release its fat. In this recipe, sliced potatoes, onions, and tomatoes are layered in a gratin dish and baked until tender, then the fish is arranged on top and finished under the broiler.
1 pound Red Bliss or Yukon Gold potatoes, peeled and thinly sliced (about 3 cups)
2 medium onions, thinly sliced (2 cups)
1 tablespoon chopped fresh savory or thyme
1 1/2 tablespoons olive oil
3/4 teaspoon salt
1/4 teaspoon freshly ground black pepper
1/3 cup homemade chicken stock (see recipe below) or low-salt canned chicken broth
2 large ripe tomatoes (1 pound total), cut into 1/2-inch-thick slices
1/2 cup dry white wine
4 large mackerel (12–14 ounces each), gutted and heads and tails removed
1/2 teaspoon herbes de Provence
2 tablespoons chopped fresh parsley
Preheat the oven to 400 degrees.
Rinse the potato slices well in cool water, then drain them thoroughly in a colander. Put the potato slices in a gratin dish, add the onions, savory, oil, 1/2 teaspoon of the salt, and the pepper, and mix well. Add the stock, and arrange the sliced tomatoes over the top.
Bake for 1 to 1 1/4 hours, until the potatoes are tender. Remove and add the wine. (The gratin mixture can be prepared to this point up to 1 hour ahead and set aside. At serving time, arrange the mackerel on top and finish under the broiler.) Preheat the broiler.
Meanwhile, make 3 horizontal slits, each about 1/4 inch deep, through the skin on both sides of each mackerel. Sprinkle the fish with the remaining 1/4 teaspoon salt and the herbes de Provence and arrange them in one layer on top of the gratin, pushing them partially into the gratin.
Place the dish under the broiler so it is about 10 inches from the heat and broil for 10 minutes. Sprinkle with the parsley and serve.
Makes 3 quarts
It takes very little work to make your own stock; mostly it is a matter of being at home for the several hours it takes to cook. A flavorful money saver that is practically fat- and salt-free, homemade stock can be frozen in small quantities and used as needed.
Chicken backs and necks are available at most supermarkets. If you don’t see them, ask the butcher to set aside some for you. I also make stock from the bones of roasted chicken or turkey.
4 pounds chicken bones (necks, backs, wings, etc.), skinless or with as little skin as possible
6 quarts cold water
1 large onion (about 8 ounces), quartered
1 tablespoon herbes de Provence
12 whole cloves
4 bay leaves
1 tablespoon dark soy sauce (optional)
Combine the bones and water in a large stockpot and bring to a boil over high heat. Reduce the heat and boil gently for 30 minutes. Most of the fat and impurities will rise to the surface; skim off as much of them as you can and discard them.
Add the onion, herbes de Provence, cloves, bay leaves, and soy sauce, if using, return to a boil, and boil gently for 2 1/2 hours. Strain the stock through a fine strainer or a colander lined with dampened paper towels. Allow to cool.
Remove the surface fat and refrigerate the stock for up to 5 days, or pour into containers and freeze.
Copyright © 2011 by Jacques Pépin. Used by permission of Houghton Mifflin Harcourt. All rights reserved.