- 3 tablespoons olive oil
- 2 cups chopped onions
- 4 garlic cloves, finely chopped
- 1 tablespoon chopped fresh thyme
- 1 10-ounce package frozen chopped spinach, thawed, squeezed dry
- 2 whole matzo sheets, finely crumbled (about 1 cup)
- 1 large egg, beaten to blend
- 1 4-pound flat-cut brisket
- 2 pounds onions, thinly sliced
- 2 1/4 cups canned chicken broth
- 3 large carrots, peeled, cut into 1-inch pieces
- 3 celery stalks, sliced
- 5 garlic cloves, peeled
- 1 tablespoon chopped fresh thyme
- 1 bay leaf
- Heat oil in heavy large skillet over medium heat. Add onions, garlic and thyme; sauté until onions soften, about 5 minutes. Cool 15 minutes. Mix in spinach and matzo. Season stuffing with salt and pepper. Mix in egg.
- Preheat oven to 350°F. Cut deep pocket in 1 side of brisket, leaving 3/4-inch border of meat uncut on remaining 3 sides. Fill pocket with stuffing. Skewer or sew pocket closed. Sprinkle salt and pepper all over brisket.
- Arrange half of onions in bottom of large roasting pan. Place brisket, fat side up, on onions. Top brisket with remaining onions. Pour 1/4 cup broth into pan. Bake brisket uncovered until meat and onions begin to brown, about 1 hour.
- Add carrots, celery, garlic, thyme and bay leaf to pan around brisket. Pour remaining 2 cups broth over. Cover pan with foil. Reduce temperature to 300°F. Bake brisket until tender, about 2 1/2 hours longer. Remove from oven. Uncover pan; let brisket stand 30 minutes. Thinly slice brisket across grain. Overlap slices on platter. Surround with vegetables from pan. Spoon off fat from pan juices; season juices with salt and pepper. Serve brisket with pan juices.