In a large cast-iron or ovenproof skillet, cook bacon over medium heat until crisp. Remove to paper towels to drain, reserving 1/4 cup drippings. Crumble bacon and set aside. , Trim beef; cut into serving-size pieces. Brown on both sides in drippings. Top meat with mushrooms, tomatoes and onion. Sprinkle with tarragon and bacon. Cover and bake at 325°, until meat is tender, 1-1/4 to 1-3/4 hours, basting twice. , Remove meat to a serving platter; keep warm. Combine cornstarch and water until smooth; add to skillet. Bring to a boil; cook and stir until thickened, about 2 minutes. Reduce heat; stir in cream. Simmer, uncovered, until heated through, 3-4 minutes. Return meat to skillet and turn to coat with sauce. If desired, sprinkle with parsley.