01 - Preheat oven to 325°F. Lightly grease a 2-quart baking dish with butter.
02 - Rinse short-grain rice under cold water until clear. Drain rice thoroughly.
03 - In a large bowl, whisk together sweetened condensed milk, whole milk, melted butter, granulated sugar, vanilla extract, ground cinnamon, and salt.
04 - Stir rinsed rice and, if desired, raisins into the milk mixture.
05 - Pour mixture into prepared baking dish. Gently stir to evenly distribute rice.
06 - Bake uncovered for 1 hour, gently stirring every 20 minutes, until set and the top is lightly golden.
07 - Remove from oven, allow to cool briefly. Serve warm or chilled, garnished with extra cinnamon if desired.