Peel and remove the pits from the peaches. Either weigh out 400 grams (14 ounces) of peach flesh or cut the peach into small cubes, until you have two lightly packed cups.
In a food processor or blender, purée the peaches with the lemon juice until the mixture is fairly smooth (it will get even smoother in the second processing). Add the sugar and sour cream and pulse just to mix.
Scrape the mixture into a shallow pan, cover, and freeze.
Once frozen, break the frozen mixture into small chunks (with a fork) and process in the food processor until the entire mixture is blended and smooth. Don’t be afraid to continue processing if some of the frozen chunks are stubborn: Extra processing makes smoother and creamier ice cream.
Serve immediately if you want soft serve or a slushy spoon drink, or scrape into a container and freeze until firm enough to scoop, at least 3 hours, or until needed.
If the ice cream freezes solid, let it soften in the fridge for 15 minutes or longer, or soften carefully in the microwave on the defrost setting, a few seconds at a time. For the best flavor and texture, serve within 2 to 3 days.
My career was sparked by a single bite of a chocolate truffle, made by my Paris landlady in 1972. I returned home to open this country’s first chocolate bakery and dessert shop, Cocolat, and I am often “blamed” for introducing chocolate truffles to America. Today I am the James Beard Foundation and IACP award-winning author of ten cookbooks, teach a chocolate dessert class on Craftsy.com, and work with some of the world’s best chocolate companies. In 2018, I won the IACP Award for Best Food-Focused Column (this one!).