Mexican crema
A lightly soured, pourable Mexican cream, milder and runnier than sour cream, drizzled over dishes.
Crema is a Mexican cultured cream, made by lightly souring cream with lactic acid cultures. It is thinner than sour cream or crème fraîche, tastes gently tangy and rich, and has more fat than sour cream. That makes it easy to drizzle over tacos, enchiladas or soups, and it rarely curdles in warm sauces. In North America it is sold in the chilled section of many supermarkets, while in German-speaking countries it turns up only occasionally in Latin American shops or through refrigerated mail order.
Substitute:
Crème fraîche thinned with a little milk or cream comes very close to crema and also holds up to heat. Sour cream thinned with some cream works too, but it is noticeably more sour and can curdle in hot dishes.