Whisk pumpkin, sweetened condensed milk, vanilla and pumpkin pie spice together in a bowl until smooth and well blended.
Whisk in the half and half.
Pour into ice cream maker and freeze according to instructions on freezer.
I use a counter-top style ice cream maker. This recipe will fill 2 ice cream makers. If you only use one counter-top style maker, cut the recipe in half. You can make the whole recipe in a traditional ice cream maker that uses salt and ice.