*What is crema?
The Mexican crema called for in this homemade blackberry ice cream recipe is essentially the same thing as French crème fraîche—which you can definitely substitute here. Less tart and tangy than standard American sour cream, they both have a thinner texture. And, unlike sour cream, they won't break down when heated, which is essential when making the ice cream custard. Take a look at the ingredients in your crema though, sometimes it has salt added. In that case, you won't need to add any to your ice cream.