Chicken Stir Fry

1 tablespoon cornstarch
1/4 cup brown sugar
1/2 cup sherry
1/3 cup soy sauce
1 tablespoon vegetable oil
1 cup sliced onions
1 cup sliced mushrooms
3 ounces snow peas
1 red bell pepper, cut into 1-inch chunks
1 yellow bell pepper, cut into strips
1 (12.5 ounce) can chunk white chicken,
    drained, cut into strips

Blend together cornstarch, sugar, sherry and soy sauce. Over high heat stir fry vegetables in oil for 2 to 3 minutes. Stir in cornstarch mixture. Add chicken. Gently toss to heat and coat.