Crema Espesa It isn't uncommon to see three of four buckets of cream in Central, West-Central and Tabascan markets: from thin, sweet and fresh to well ripened, thick and tangy. It's all heavy cream — not the light, low-butterfat cream that is cultured for sour cream here — so it has a richer, glossier texture. And you can bet it's not pasteurized, because the process would have killed the natural bacteria that perserves and thickens the riper cream. To me, this thick, ripe cream (similar to French crème fraîche) is one of the great pleasures of Mexican cooking. Mixing a little milk or cream into our commercial sour cream is a passable substitute here, but nothing like the smoother, less acidic taste of this recipe