1. Preheat oven to 400 degrees. Butter a shallow 2-quart baking dish; set aside.

2. In a medium-size heavy-bottom saucepan, combine rice, 3 cups milk, 1/4 cup sugar, and salt. Cook over medium heat, stirring frequently, until thick and creamy, about 30 minutes.

3. In a liquid-measuring cup, whisk together the egg yolks, remaining milk, and 1 teaspoon pure vanilla extract. Stir into rice. Add raisins and cinnamon. Cook until raisins are heated through, about 2 minutes. Pour rice mixture into the prepared baking dish. Set aside.

4. In the bowl of an electric mixer, whisk the egg whites until foamy. Increase speed to high, and gradually add the remaining 1/2 cup sugar, cream of tartar, and remaining 1/2 teaspoon vanilla. Beat until stiff but not dry, 3 to 4 minutes. Using a rubber spatula, spoon meringue on top of the rice, covering entirely. Transfer to the oven, and bake until the meringue is golden brown, about 5 minutes.