Stir together 1/2 cup brown rice, 1 cup water, and 1/4 teaspoon salt in a medium saucepan. Bring to a boil over medium-high heat. Reduce heat to low and simmer covered until water is almost all absorbed, 15-20 minutes.
Stir in 2 cups whole milk and bring to a simmer over medium-high heat. Reduce heat to medium-low and continue to simmer, uncovered, until the pudding is thick and clings to the spoon, about 30-40 minutes.
Remove saucepan from heat and stir in 1/4 cup maple syrup, 1 teaspoon vanilla and 1/4 teaspoon cinnamon. Cool slightly and serve warm or chilled. Add additional whole milk if the pudding has thickened too much. Top with fresh or dried fruit or nuts as desired.
Notes
To use white rice instead of brown rice: Substitute 1/2 cup long or medium grain white rice for the brown rice. Follow the recipe as written. The white rice may cook slightly more quickly than brown rice, but cooking times should not vary too much in this case.