Step 1
Preheat oven to 325 degrees F (165 degrees C).
Step 2
Mix paprika garlic powder black pepper sea salt and cayenne pepper in a bowl until thoroughly combined. Set spice mixture aside.
Step 3
Heat olive oil in a large skillet over medium heat; cook and stir mushrooms and shallots until mushrooms have released their liquid 5 to 8 minutes. Set mushroom mixture aside.
Step 4
Melt 1/4 cup margarine in a large skillet over medium-high heat and stir in 1/4 cup Worcestershire sauce. Rub beef brisket thoroughly with spice mixture; place brisket into the margarine and Worcestershire sauce.
Step 5
Brown the brisket well on all sides about 5 minutes per side. As the Worcestershire sauce cooks into the brisket pour in more about 1/2 cup at a time until 1 1/2 cup Worcestershire sauce has been added.
Step 6
Place a rack into a heavy Dutch oven; place the brisket onto the rack. Pour in the Worcestershire sauce pan drippings red wine water garlic and beef broth. Top the brisket with the mushroom mixture. Drizzle 1 tablespoon Worcestershire sauce over the mushrooms and top with 2 tablespoons sliced unsalted margarine.
Step 7
Cover the Dutch oven and bake brisket in the preheated oven for 3 hours. Reduce heat to 300 degrees F (150 degrees C) and bake 1 more hour. Reduce oven temperature to 225 degrees F (105 degrees C) and bake 1 additional hour. Baste with pan drippings every hour.
Step 8
Let the brisket rest for about 20 minutes before slicing thinly across the grain. Serve with pan gravy.