Prawn gumbo

Ingredients

• ½ tablespoon vegetable oil
• 1 onion, finely chopped
• 2 celery sticks, finely chopped
• 2 green peppers, deseeded and finely sliced
• 1 red chilli, deseeded and finely chopped
• 2 cloves garlic, peeled and finely diced
• 1 x 400g can chopped tomatoes
• 200g okra, topped and tailed, and roughly chopped
• 150g wholegrain rice (uncooked weight)
• 800ml vegetable stock, made with 1 reduced-salt stock cube
• 300g cooked king prawns
• Freshly ground black pepper
• Large handful flat leaf parsley, roughly chopped