½ teaspoon ground cinnamon, plus more for sprinkling
1 cup rice
1 teaspoon vanilla extract
1 teaspoon orange zest (if you have it), plus a little more for serving
Small piece of a chocolate bar (chill it for a few minutes if you can)
Generous pinch fine sea salt
Combine 5 cups of the milk, cream, sugar, brown sugar, cinnamon, and salt in a medium saucepan and bring to a gentle boil over medium-low heat (make sure to watch it because that milk can boil over in a heartbeat!).
Stir in the rice, return to a boil, reduce the heat to medium-low, and simmer, stirring often, until the rice releases its starch and the mixture has thickened, 30 minutes (the pudding will continue to thicken as it cools).
Remove from the heat and stir in the vanilla and orange zest. Press foil, plastic wrap, or parchment paper on the surface of the pudding and let it come to room temperature, about 30 minutes (or chill for an hour or two if you like cold rice pudding).
Stir in the remaining ⅓ cup of milk to loosen, and feel free to add more milk or cream to get the consistency you want. Divide among bowls, grate some chocolate and orange zest over the pudding, and sprinkle with cinnamon if you like.