Prawn & Broccoli Stir Fry

This is a very quick mid week meal.  In half an hour flat you will have a deliscious and healthy plate of food.

500g shelled prawns(tiger prawns are best for this recipe)
1 medium onion thickly sliced
2 carrots, peeled cut lengthways and sliced
1 celery stick, sliced
1 broccoli cut into small florets
1 broccoli stem, peeled and sliced
1 tomato peeled and thickly chopped
2 cloves garlic crushed
1 inch ginger finely chopped
1 tablespoon oil
2 tablespoons oyster sauce
2 tablespoons soy sauce
1 cup chicken stock
1 teaspoon cornflour diluted in little water.
Freshly cracked black pepper

Heat the oil in a large frying pan or wok,  add onions, celery, garlic, broccoli stem, and ginger and stir fry. Add broccoli and stock, and cover. Simmer for 5 minutes.  Add prawns and stir. Thicken liquid with diluted corn flour, add soy sauce and oyster sauce and stir. Finally add tomatoes and freshly ground black pepper stir and serve with fluffy white rice or noodles (see recipe http://marthesefood.blogspot.com/2011/12/veal-rolls-with-fluffy-fragrant-rice.html)