1/4 cup vegetable oil
1 pound lean beef brisket
1 large onion, chopped
1 (16 ounce) can mushroom soup
1 (4 ounce) can tomato paste
1 tablespoon dried sage
1 tablespoon dried oregano
1 1/2 teaspoons salt
1 teaspoon dried basil
2 tablespoons dry mustard
1 cup whole milk
1/4 cup butter
1 pound Swiss cheese, sliced
Heat oil in a large skillet over medium heat. Stir in beef, onion, mushrooms, tomato soup, tomato paste, sage, oregano, salt, basil, dry mustard and whole milk. Saute until beef is browned and beef is transparent, about 5 minutes.
Remove pan from heat. Pour broth mixture over beef. Stir in butter.
Slice Swiss cheese around the edges to keep it in place. Do not cut in slices too large.