5-6 pound first-cut brisket, trimmed
  with a thin layer of fat on one side
2 teaspoons of kosher salt
Fresh ground pepper
3-4 Tablespoons of all purpose flour

3 Tablespoons of high smoke point oil, ie canola
8 medium yellow onions
4-5 Tablespoons of tomato paste (6 oz can)
4 garlic cloves, peeled and thickly sliced
1 carrot, peeled and halved lengthwise

Equipment needed: A large heavy pot or Dutch oven with a lid.
1.  Preheat oven to 375 degrees.  Peel the onions and thickly slice them crosswise (not through the root).  Put onion slices into a big bowl and separate them into rings.  Set aside.
2.  Season the brisket on both sides with salt and pepper.  Dust with flour on both sides.
3.  Heat oil in the pot over medium heat.  Brown the brisket all over.  If the brisket is larger than the pot, flip it over until you've got a nice brown color and crusty bits over most of the meat.  Transfer the brisket to a platter and add onions to the pot.
4.  Turn the heat up a bit and cook the onions, stirring often with a wooden spoon and scraping up the browned bits on the bottom of the pot, until the onions are golden brown, but to yet caramelized, about 15 minutes.
5.  Turn off the heat.  Place the brisket, fat side down, on top of the onions.  Using a small butter knife of something similar, coat the top and sides of the brisket with tomato paste, as if you were frosting a cake.  (Use the whole can if brisket is very large)
6.  Tuck the carrot halves and garlic around the outside of the meat and cover the pot and cook for 1 1/2 hours.  
7.  Pull the pot out of the oven and turn the oven down to 325 degrees.  Transfer the brisket to a cutting board.  Using a very sharp knife, cut the meat across the grain, into thin slices.  Carefully return the slices tot he pot, as if you are reassembling the brisket.  Place your knife between each slice to make sure some of the liquid get between all the slice.  Slightly tilt the slices to one side to ensure they stay down in the liquid.  Cover the pot and return it to the oven for another two hour until fork tender Check the pot one of twice during the cooking.  If it looks dry add 2-3 teaspoons of water.
8.  Brisket is ready to serve or it can be refrigerated for up to three day.  Flavors only better over time.  
9.  This brisket freezes well.