Risotto is a method of rice cookery in northern Italy. In other parts of Italy where rice is also eaten the prepared dish is called riso, and it is not cooked by this special method. The most common rice in Italy are the many varieties of the short grain rice Oryza sativa japonica.
My risotto recipes call for one variety of short grain rice called Arborio rice, a rice that can be found relatively easily in many supermarkets now and certainly in an Italian market. There are four basic varieties of rice used in Italian cooking: riso fino, a round medium grain rice that includes a subcategory called vialone nano, a rice favored by Venetian cooks in making minestra and risotto; riso semifino, a longer grain rice used in minestrone; riso superfino, which includes the familiar Arborio rice; and riso comune, a glutinous short grain rice, which includes balilla rice, used for desserts. In northern Italy one is likely to find a hybrid rice called carnaroli or maratelli, a rice older than six months and a cross between vialone and lencino which are both japonica type rice, used for risottos. If you are unable to find these rices, use a short grain Japanese or medium grain Spanish rice but never use converted rice.
The secret to a perfect risotto is a combination of two elements: a flavorful broth and the broth added to the rice correctly. The goal in risotto is to have a sticky, creamy rice derived from the starch in the rice, and never from the addition of cream. Unlike a pilaf, where one rinses the starch from the rice and never touches the rice while it is cooking, in a risotto one leaves the starch and is almost constantly stirring the rice. A risotto is the opposite of a pilaf.
A risotto begins with melting butter or heating olive oil in a heavy saucepan. I like using the Le Creuset enameled cast-iron saucepan. Then a soffritto is made, which is a mixture of very finely chopped vegetables that is cooked, if it is called for in the recipe. The rice is now added and cooked for a couple of minutes while stirring. Now one begins to add broth. Start with about half of the broth called for in the recipe, unless instructed otherwise in that recipe, and pour it into the rice. Stir as you add the broth, then reduce the heat to a simmer, and continue stirring frequently as the broth is absorbed by the rice. Continue adding half of the remaining broth, stirring as you do, until the rice is creamy and tender. Zeno’s Paradox is avoided by making the last addition of broth the last remaining 1/4 cup. This is the single most important feature of a risotto: the broth is never added all at once. (On the other hand, I understand that some Italian and even Venetian cooks add the broth all at once). The reason I like adding broth a little at a time is that it gives you better control over the final texture. The time it takes to cook a risotto depends on the age of the rice and the temperature you cook it at, so anywhere between 30 minutes and 1 1/4 hours is possible.