Put rack in middle of oven and preheat oven to 350 degrees.

Pat brisket dry and sprinkle with salt and pepper. Heat oil in a 6- to 8-quart, wide, heavy, ovenproof pot over moderately high heat until hot but not smoking. Brown meat well on all sides, about 10 minutes total. Transfer to a platter.

Add onions and bay leaf to fat remaining in pot and cook over moderate heat, stirring occasionally, until onions are golden, 10 to 12 minutes. Remove from heat and transfer half of onions to a bowl. Arrange brisket over onions in pot, then top with remaining onions. Add beer, bouillon cube and vinegar (liquid should come about halfway up sides of meat; add water if necessary) and bring to a boil.

Cover pot. Transfer to oven and braise until meat is very tender, 3 to 3-1/2 hours. Let meat cool in sauce, uncovered, for 30 minutes.

Transfer brisket to a cutting board. Skim off any fat from sauce, discard bay leaf and season sauce with salt and pepper. Slice meat across the grain and serve with sauce.

Notes: Choosing brisket: There are two brisket cuts available in most supermarkets, and the labeling can often be confusing. If you prefer a more marbled piece of beef, look for the thicker end, known as the point half, which may be labeled the front, thick, second, or nose cut. The thinner, leaner end of the brisket is the flat half, sometimes called the first or thin cut.

Preparing ahead: The brisket actually improves in flavor if braised 2 days ahead. Cool the meat in the sauce, uncovered. Cover the meat's surface with parchment paper or wax paper, then cover the pot with a lid, and refrigerate. Remove any solidified fat before reheating. To reheat, slice the cold meat across the grain and arrange in a shallow baking pan. Spoon the sauce over the meat and reheat, covered, in a 325-degree oven for 45 minutes. Do not use a large roasting pan for the recipe. The wider the pan used to oven-braise the meat, the more water that must be added, resulting in a too-thinly flavored sauce.

Source: Marcela cribbed this from the 28 Dec 2004 FOODday, which in turn cribbed it from Ruth Reichl's new Gourmet Cookbook. We plan to prepare this for the 2006 MNF Sunriver trip.
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