Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1 1/2  pounds        beef flank steak
     1/4  cup           white wine
   1      tablespoon    soy sauce
   1      clove         garlic -- minced
   1      10.5 oz can   beef broth
   1      tablespoon    catsup
   1      teaspoon      prepared mustard
   1      tablespoon    instant minced onion
   2      tablespoons   cornstarch
   2      tablespoons   water
     1/4  pound         fresh mushrooms -- sliced

Preparation:

Place steak in crockpot. Combine wine, soy sauce, garlic, broth, catsup, mustard and onion; pour over steak. Cover and cook on low for 6 to 8 hours. Dissolve cornstarch in water; stir into pot. Add mushrooms. Turn to high; cover and cook on high 20 to 30 minutes.