3 to 4 pound flat cut brisket
2 Tbsp. olive oil
1 large yellow onion, sliced
1 can cream of mushroom soup
1/2 cup water
3/4 cup brown sugar
1/4 cup vinegar
1 tsp. Worcestershire sauce
1 tsp. mustard
1/4 cup Marsala wine
In a Dutch oven on top of the stove, brown meat in 2 Tbsp. oil on both sides. Add sliced onions. Blend together other ingredients in a bowl and pour over meat. Cover and simmer for 2-1/2 to 3 hours or until meat is very tender. Add water to moisten pot as needed during the cooking process. Allow to cool for a few minutes, then thinly slice meat across the grain.