1vanilla beansplit in half lengthwise & seeds scraped
Make the rice pudding by combining the milk, rice, and salt together in a heavy-bottomed saucepan over medium-high heat.
Split the vanilla bean pod in half with a knife. Using the back of the knife, scrape the inside of the vanilla bean pod to remove the seeds and place them into the milk and rice. Whisk until well combined.
Bring to a boil then reduce heat to low and simmer and cook, stirring often, until the rice is softened, 30-35 minutes.
Combine the brown sugar and egg together in a bowl; whisk until combined.
Temper the mixture with about a 1/2 cup of the rice/milk mixture, a tablespoon at a time, while whisking vigorously to incorporate.
Add the tempered mixture into the rice and milk mixture along with the cinnamon then stir until mixed thoroughly.
Cook on low, stirring often, until thickened, or about 160 degrees F., making sure not to let it boil because it will curdle.