People have been making ice cream far longer than the invention of electricity so there’s no reason you can’t make ice cream and sorbets at home without a machine.
The advantage to using an electric or hand-cranked machine is that the final result will be smoother and creamier. Freezing anything from liquid-to-solid means you’re creating hard ice crystals, so if you’re making it by hand, as your ice cream or sorbet mixture freezes, you want to break up those ice crystals as much as possible so your final results are as smooth and creamy as possible.
Machines are relatively inexpensive nowadays with models costing less than $50, and yes, I’ve seen the ball, but if I started tossing one of those around the streets here in Paris, I’d probably get even more strange looks than I normally get. (Plus you’ll need to lug some rock salt home as well.)
But not everyone has the space or the budget for a machine, so here’s how you can do your own ice cream at home without a churner. I recommend starting with an ice cream recipe that is custard-based for the smoothest texture possible. You can use my Vanilla Ice Cream or another favorite, or even this Strawberry Frozen Yogurt recipe using Greek-style or drained yogurt. The richer the recipe, the creamier and smoother the results are going to be.
Ice cream made this way is best eaten soon after it’s made—which shouldn’t be a problem.