Generously salt and pepper brisket. In a heavy pot over medium high heat, add 2 T olive oil. When hot, add brisket and sear well on all sides and ends. Rest meat on sheet pan. Add chopped onion, carrot, celery and 2 garlic cloves to the pot. Saute for 3-5 minutes and then deglaze with 1/3 cup red wine. Place brisket on vegetables and add 3 cups of beef stock, 2 cups of red wine and tomatoes. Add bouquet garni and bring to a boil for 2-3 minutes. Place lid on the pot and cook for 3-4 hours at 350 degrees. After one hour, turn meat over and continue to cook.
To make gremolata, heat 2 T olive oil, remaining 2 garlic cloves and heat in small sauté pan. When garlic begins to sizzle, remove from heat and set aside to cool. In a medium bowl, place zest of lemon, chopped parsley, pinch of salt and pepper and mix together. Add garlic olive oil, squeeze of lemon juice and combine in bowl. Set aside to serve on top of brisket as garnish.
After 2 1/2 hours check to make sure there is enough liquid in the pot. Add 1-2 cups of beef stock as needed. Continue to cook until meat is tender and falls apart. Remove bouquet garni and set meat on sheet pan. Cover with foil. Skim excess fat off sauce and discard. If sauce needs thickening, reduce over high heat or add 2 T corn starch, pre-mixed with water to avoid lumps. Salt and pepper to taste. Slice brisket and serve immediately with sauce and gremolata. Serve with mashed potatoes or polenta. Serves 4.