Braised Fish with Fennel and Tomato
Because fish fillets, unlike dense cuts of meat, cook quickly, the braising liquid is infused with flavor first, as in this dish, which blends tomatoes, fennel, garlic, and lemon.
If the skin on your lemons is not too bitter (check by tasting a washed one), you may want to leave it on; this will help the slices hold their shape. Otherwise, remove the rind before slicing.
Buy 4 fish fillets of the same size (4 to 5 ounces each) so they cook at the same rate. A 1 1/2-inch thickness is ideal, allowing the fillets to cook evenly. Much thicker and the exterior could toughen before the center has cooked.