The rice is, at it's most basic, a pilaf with a blended puree of tomato, garlic and onion forming the basis of the stock. As far as quantities for each cup of medium grain rice a single plum tomato, a clove of garlic and about 1/4 of a medium onion along with a splash of water to allow the blender turn make up the purée. I also like to add about an inch of azafran to the dish for both colour and taste.
Browning the rice
This is the unusual part of the procedure. The rice must first be browned in some vegetable oil. This is not the gentle sweating that is the starting point for a risotto, the rice is fried under medium high heat until toasted and golden brown. This is a very counter intuitive procedure to anyone more familiar with European cooking, but stick with it.
Once the rice is golden brown the purée is introduced and the frying continues for another couple of minutes until the tomato has cooked out a bit.
This ingredient has been the cause of quite a bit of confusion for me! Every time I had this rice in a restaurant, there was something savoury in it I couldn't identify. I would as a friend:
"There is something unusual in this, what is is", the answer always was
"Are you sure? It doen't taste like saffron"
This went on for some time and I made rice a number of times, but was never entirely happy and could never match the taste of what I had been served.
Finally in the supermarket I spotted it! Azafran.
It is the root of the safflower plant, resembling ginger root but smaller with a yellow skin. Like saffron proper it is a very effective dye (preparing it will make your fingers look like an 80 a day smoker's, and it will stain everything it touches), but it doesn't have saffron's medicinal taste, it's somehow both lemony and meaty.
Finishing the rice.
Once the purée has cooked out slightly the liquid can be added. I find that for each cup of rice about two cups of liquid are about right, but allow for any liquid you added to the blender in the beginning, so in this case I used just shy of two cups of light chicken stock (or water).
At this point the pan is covered and the rice left to cook undisturbed over a low heat. It should take about 15 minutes to cook.
About 5 minutes from the end of the cooking time some peas can be added for colour. You may have noticed that I didn't add any chile. I don't think the rice should have chile in it if it being used as an accompanying dish. If you are going to add chile it's best to add some thin rounds of serrano along with the peas - adding the chile to the tomato purée dulls the red colour and if the chile was added before the peas the it's colour will have muddied by the time the dish is cooked.
After the 15 minutes have elapsed turn off the heat and leave the rice covered for a further 10 minutes to finish cooking. If you find you have too much or too little water you can do whatever manipulations are necessary at this point.
Garnish with some corriander and eat.