Chinese Clam Soup

Ingredients

• 1/2 lb chicken fillet, cut into thin strips
• 1 teaspoon soy sauce
• 1/2 teaspoon cornstarch
• 1/2 teaspoon sugar
• 1/2 teaspoon black pepper
• 5 cups chicken stock
• 5 Chinese mushrooms, soaked for 20 minutes, drained and cut into strips
• 3 slices ginger
• 1 (8 ounce) can clams
• 1 spring onion, finely chopped
• 1 Chinese celery, finely chopped