2 cups heavy cream
1 cup milk
2 1/2 tsp ground cinnamon
1/2 cup plus 1/2 cup white sugar, divided
10 large egg yolks
Combine the cream, milk, cinnamon and 1/2 cup sugar in a medium-sized sauce pot and bring just to a simmer over medium heat.
Whisk the egg yolks with the remaining 1/2 cup sugar and pinch of salt. Pour about a third of the hot cream mixture into the yolks, whisking constantly as you pour. Return this egg-cream mixture back into the remaining hot cream mixture in the saucepan and cook, stirring constantly, until the custard thickens enough to coat the back of the spoon. The temperature of the custard should not exceed 180°F.
Strain the custard into a 2 quart container and cool to room temperature, stirring occasionally, then cover and refrigerate until very cold, about four hours to overnight.
Process in an ice cream maker, according to the manufacturer’s instructions. After processing, transfer to an airtight container and freeze until ready to serve.