Heat the oven to 300 degrees F. Have ready a shallow, 2-quart baking dish
. When the rice is cooked, drain it well in a fine-mesh sieve and put it in the baking dish. Add the brown sugar, raisins, vanilla, cinnamon, nutmeg, and salt to the rice. Wipe out the rice saucepan and add the evaporated milk and heavy cream. Over medium-high heat, bring the liquids barely to a boil and then pour them into the baking dish. Stir the mixture a few times until the ingredients are well dispersed and the sugar has dissolved. Bake until the top is browned, the liquid is reduced and thick, and the rice is tender, 1-1/2 to 2 hours.