01 - Combine the rice, whole milk, heavy cream, lemon peel strips, cinnamon stick, and salt in a medium saucepan. Bring to a gentle simmer over medium heat, stirring occasionally to prevent sticking.
02 - Reduce heat to low and simmer for 25 to 30 minutes, stirring frequently, until the rice becomes tender and the mixture thickens considerably. Remove and discard the lemon peel and cinnamon stick.
03 - Stir in the granulated sugar, butter, and vanilla extract. Continue cooking for 2 to 3 minutes, stirring until the sugar completely dissolves and the butter melts.
04 - Whisk the egg yolks in a separate bowl. Gradually ladle small amounts of the hot rice mixture into the yolks, whisking constantly, to warm the yolks without scrambling them.
05 - Return the warmed yolk mixture to the saucepan. Cook over low heat, stirring continuously, for 2 to 3 minutes until the custard coats the back of a spoon. Do not allow the mixture to boil.
06 - Pour the custard evenly into individual ramekins or a large shallow serving dish.
07 - Mix together the remaining 2 tablespoons granulated sugar and ground cinnamon. Sprinkle evenly over the surface of the custard.
08 - Allow the rice custard to cool completely to room temperature. Serve warm or refrigerate until chilled before serving.