What is the history behind manzanilla olives containing a pimiento center?

Once the pit is removed from any variety of pitted olives, as you say yourself, they can be stuffed with all kinds of different things. You then ask why is it always pimiento? Well, it isn't always pimiento. It is, if you are referring to Manzanilla olives, because the recipe for Spanish stuffed olives includes using pimiento (the spanish word for pepper) Who came up with this recipe, would be impossible to find (in my humble opinion) because it is so old. Most likely, it was someone experimenting with stuffing olives, tried it with pimiento and decided it tasted good. I guess a lot of other people did as well, so it caught on, to become the Manzanilla Olive from Spain. So, if it is pimiento you are interested in, here are a few facts. As I already said, it was Spain who started using it to stuff olives. It is also where paprika comes from, actually, that is what most of the crop is used for. Another fact is, allspice comes from the Pimento tree.

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