Peach nectar is a sweet, intensely flavored drink that's usually found on the international food aisle, with the fruit juices, or with cocktail mixes.
Combine first 3 ingredients in a medium bowl.
Process peach mixture, in batches, in a food processor until smooth, stopping to scrape down sides. Set aside.
Whisk together yolks and milk in a heavy saucepan over medium heat; cook, stirring constantly, 20 minutes or until mixture thickens and coats a spoon. Do not boil.
Remove from heat; whisk in peach mixture, half-and-half, lemon juice, and ground cinnamon. Cover and chill 4 hours.
Pour mixture into freezer container of a 6-quart electric ice-cream maker. Freeze according to manufacturer's instructions. (Instructions and times will vary.) Garnish, if desired.
Note: For testing purposes only, we used a White Mountain 6-Quart Electric Ice Cream Freezer.
I think this ice cream would have turned out great if in the recipe it didn't tell you to add lemon juice to milk, because if you do that it curdles and becomes inedible and disgusting.