crema is a fairly obvious cognate for ‘cream’ but that’s not what it always means. In fact, the conventional U.S. meaning of creme (as a standalone word) would be crema de leche in Spanish. But both English and Spanish use ‘cream’ (crema) in multiword combinations to provide more precise meaning BUT often menus don’t include the additional qualifying words and thus leave one guessing what crema might be.
While crema means conventional English notion of cream in Mexico as well crema has become part of foodie vocabulary in U.S. as the Mexican version of sour cream (sorta) or crème fraîche (sorta). Sour cream in Spanish seems to be crema agria but I can’t determine exactly where this would be used (for instance, is it used in Mexico given everyone just says crema).
But then we move on to another usage: crema catalana which on some menus would merely be listed (presumably under postres) as just crema. The qualification of Catalana (thus Catalan cream in literal English) doesn’t tell a non-Spaniard much, but finding this is another term for crème brûlée would at least clue most English-speaking foodies. In fact, crema catalana is almost entirely what one gets in searches for crema. Meanwhile, as another sweet, GallinaBlanca reminded its readers that crema pastelera is one “meaning” of crema (and presumably sometimes again just crema would be used without the modifier to achieve this meaning); again this is easy for foodies since it literally translates to pastry cream. While there are variations of pastry cream it is mostly the same basic recipe.
And then we have this: crema de calabcín which is a soup made with zucchini, onion, cheese and liquid cream. While this is the only term GallinaBlanca provides in its dictionary I’ve seen lots of other variations on menus and sometimes just as the standalone word crema (usually with clear implication it’s a soup). Now again, this matches English usage, e.g. cream of mushroom soup (we, of course, add the soup, hardly needed as qualifier and it appears sopa (the literal soup) doesn’t appear as a qualifier in Spain. And I’ve never seen sopa de crema whereas you do see its English equivalent (cream soup) on menus in U.S. which, presumably, would confuse a Spanish speaker a bit.
So the exact meaning of crema on a menu may involve some guesswork but it probably resembles a fairly similar usage in Spain. The one thing it probably doesn’t mean (while it could literally) is cream for coffee as that almost always will just be de leche.
However, additionally, one place Spanish is different than English in regards to ‘cream’ is crémor tártaro which you would probably, correctly, guess is cream of tartar. This is curious too because it’s an instance in English of using the x of y phrasing which is common in Spanish but usually occurs as y x in English.