Take a medium saucepan. Split the vanilla bean in half and scrape out the seeds. Combine vanilla bean seeds with rice, milk and cream and place in the saucepan.
Bring milk mixture to a simmer over low heat, stirring occasionally, and cook until the liquid reduces by at least half, about 30 minutes. The mixture should be roughly 2/3 rice and 1/3 liquid.
In a medium bowl, whisk together the egg and sugar until smooth. Pour in a small amount (approximately 1/2 cup) of the milk from the rice while whisking constantly. Stirring with a whisk, stream the sugar mixture back into the large pot.
Cook over medium-low heat until the pudding bubbles and thickens enough to coat the back of a spoon. Remove from heat and transfer to a separate bowl to cool.
Store, covered, in the refrigerator.