1 first cut beef brisket 5 to 6 pounds
¼ cup vegetable oil
Salt and pepper
4 large Spanish onions (about 3 pounds) thickly sliced
2 garlic cloves sliced
3 carrots chopped
3 celery chopped
Trim most of the fat from the brisket (first cut only has fat on one side).
In a heavy-duty (cast iron) skillet heat the vegetable oil over moderately high heat.
Season the brisket with salt and pepper, dredge with flour and place in the skillet.
Place brisket fat side down and cook until brisket is well browned. Turn over and over and cook until the second side is well browned and transfer to a platter.
Lower the heat in the skillet to moderate, add the onions, salt, and cook, stirring occasionally, until the onions have softened and turned golden.
Make a bed of the onions in the bottom of the slow cooker, rub the brisket on both sides with the tomato paste (like icing a cake) and place on top of the onions.
Scatter the garlic, carrots, and celery on top of the brisket
Cover the slow cooker and cook under low heat until the meat is fork tender (6 to 6 ½ hours).
Alternatively, cover the skillet and place in pre-heated 325-degree oven for 31/2 to 4 hours.
Tent and let the brisket stand for ¾ hour. Slice the brisket against the grain into ¼ inch slices and serve on a bed of onions and vegetables.
Prepare the brisket a day in advance and let sit overnight in the refrigerator. It will mellow and be even better the next day.