1. Heat the oil in a frying-pan and fry the onion for 5 minutes. Add the garlic and rice. Stir and leave it to cook for a few minutes until the rice becomes translucid.
2. Add the tomatoes and the shrimps. Sprinkle with saffron and pour the hot water on. Salt and pepper. Cook at a low temperature for 15 minutes, stirring from time to time.
3. During this time, preheat the oven to 180 °C.
4. Cut off the tops of the peppers and take out the pips. Arrange the peppers in the square dish and garnish them with cooked rice. Replace the tops.
5. Place in the oven for 35 minutes.