Rinse the rice in a fine mesh strainer under cold water for about 30 seconds, swirling with your hand. This removes excess surface starch and helps give you a creamy rather than gluey pudding. Drain well.

Combine the rinsed rice, water, and 1/2 cup of the whole milk in a medium heavy-bottomed saucepan over medium heat. Bring to a gentle simmer, stirring once or twice. Once the liquid is mostly absorbed, about 4 to 5 minutes, the rice will look thick and starchy.

Reduce the heat to medium-low. Add the remaining 3 cups of whole milk, the maple syrup, cinnamon, and salt. Stir everything together and bring back to a gentle simmer. You want small, steady bubbles around the edges, not a rolling boil.

Cook uncovered, stirring every 3 to 4 minutes, for 28 to 32 minutes. Each time you stir, scrape the bottom and sides of the pan so nothing sticks. The pudding is ready when it is thick and creamy and coats the back of a spoon, but still pours slowly from the spoon. It will look a little loose, and that is correct because it thickens as it cools.

Remove the pan from heat and stir in the vanilla extract. Taste and add a small drizzle more of maple syrup if you want it sweeter.

Spoon into bowls and serve warm. Drizzle each bowl with a little extra maple syrup, scatter the toasted pecans over the top if using, and add a pinch of freshly grated nutmeg. For a cold version, press a piece of plastic wrap directly onto the surface and refrigerate until chilled.