With lamb, less is more; strong flavor enhancers such as acidic marinades, aggressive seasonings and complicated sauces detract more from lamb's mild flavor than they contribute to it -- with the exception of brines. Brines comprise salt and water, and increase lamb's juiciness by helping prevent moisture loss during cooking. Brines also let you incorporate lamb-loving spices such as garlic, rosemary and thyme into the meat without the risk of overpowering it. Don't salt lamb after brining it or you'll negate the brine's moisture-retaining effects and over-season the meat.
Mix table salt with 1 gallon of water in a large stockpot or saucepan. Use 1/2 cup of salt per gallon when brining 1 to 2 pounds of lamb; use 3/4 cup of salt when brining 2 to 4 pounds of lamb; use 1 cup of salt per gallon when brining 4 pounds or more lamb.
Heat the salted water on the stove over medium heat until the salt dissolves, stirring occasionally. Turn the heat off and cover the brine to keep it warm.
Add flavoring ingredients, herbs and spices to the brine, if desired. You can use any herbs and spices you like; classic lamb spices include garlic, rosemary, cumin, thyme and allspice.
Bring the brine to a boil, stirring occasionally, then turn the heat off. Let the brine cool to room temperature, then transfer it to the refrigerator.
Cool the brine in the refrigerator until it is cold, about 1 hour. Place the lamb in a plastic or glass container large enough to hold it and the brine.
Pour the brine over the lamb and cover the container with a lid or plastic wrap. Place the lamb in the refrigerator.
Brine 1 to 2 pounds of lamb for 2 hours; brine 3 to 4 pounds of lamb for 4 hours; brine lamb that weighs 4 to 6 pounds for 6 hours. Brine lamb weighing 6 pounds or more for 12 hours.
Take the lamb out of the brine 45 minutes to 1 hour before cooking it and let it reach room temperature. Wipe off the excess brine and any whole spices or other flavoring ingredients; they've already served their purpose, and cooking the lamb with them won't improve the taste.