Ingredients
7 Quarts hot water
2 Cups coarse pickling salt
1/4 Cup dry mustard
2 Tablespoons pickling spice
10 garlic, plus 10 cloves, crushed
1 Teaspoon freshly ground pepper
8 Pounds beef brisket
2 ribs celery, quartered crosswise
2 onions, quartered
5 large red potatoes, halved
3 carrots, peeled and cut crosswise into thirds
3 parsnips, peeled and cut crosswise into thirds
3 turnips, peeled and quartered
1 cabbage, cut into 6 wedges 

Directions
In an 8-quart nonreactive container, stir together hot water, pickling salt, dry mustard, pickling spice, whole garlic cloves, and pepper; let cool. Add beef, and top with a plate to weigh it down and keep it submerged. Let soak in brining liquid for at least 3 days and up to 6 days in the refrigerator. 

Rinse brisket under cold water; place in a large pot with remaining crushed garlic cloves, celery, and onions. Add enough water to cover. Bring to a boil, skimming scum from surface. Cover pot, and let cook for 2 hours.
 
Uncover, adding potatoes, carrots, parsnips, turnips, and cabbage. Cover, and continue to cook until the meat and vegetables are tender, about 1 1/2 hours more. 

Source:  www.marthastewart.com