If you can’t find or simply don’t have any crème fraîche on hand, you can use sour cream instead. It contains almost the same amount of sugar and just a little less fat. Since fat is an indicator of taste and flavor, add more than what the recipe calls for if you substitute sour cream for crème fraîche in order to get the right consistency and richness. For cold dishes you can even use cream cheese, though it’s less sour than crème fraîche. Add some lemon juice for a hint of acidity.

creme fraiche vs cream cheese
creme fraiche vs cream cheese