Combine 1/4 cup flour, 1/4 teaspoon salt, and pepper. Dredge brisket in the flour mixture.
Brown the brisket in a tablespoons hot oil in a large Dutch oven; remove brisket, reserving drippings. Set brisket aside.
Saute the onion, garlic, and mushrooms in the drippings in the Dutch oven until tender. Add 2 tablespoons flour and the remaining 1/4 teaspoon salt, stirring constantly. Stir in the chili sauce and wine.
Return the brisket to the Dutch oven. Cover and bake at 325 degrees for 3 1/2 to 4 hours or until the meat is tender.