In Spanish, peanut butter is called mantequilla de maní. The word mantequilla translates to butter, and maní means peanut. So, when you combine these two words, you get mantequilla de maní, which directly translates to peanut butter in English.
Here’s a simple example of how you might use it in a sentence:
Me gusta comer pan con mantequilla de maní. (I like to eat bread with peanut butter.)
This term is widely understood in most Spanish-speaking countries, although in some regions, you might also hear it referred to as crema de cacahuate, where cacahuate is another word for peanut.