This doesn't answer your question per se, but it does answer the question partially.

I remember hearing somewhere that a major reason why ham is ubiquitous in Spanish cuisine is because it was an effective way of showing folks that you weren't a practicing Jew or Muslim in Spain after Muslim rule.

Now I couldn't recall where exactly I had heard it, and the rules specify I am not a source, so after Googling "why do spaniards eat so much pork" I found this bit of supporting evidence:

Spanish enthusiasm for pig meat stems in part from pork’s past importance as a symbol of cultural identity. Because Moors and Jews did not eat it, Christians saw the meat as more than simple nutrition. In sixteenth-century Spain, pork eating was an acid test faced by Spanish Moriscos and Marranos who publicly claimed conversion to Christianity. Conspicuous pork avoidance could result in an appearance before the tribunals of the Inquisition. - http://www.cambridge.org/us/books/kiple/hogs.htm

Not a historian, but I noticed that Ziryab/Zaryab doesn't appear anywhere in the replies yet; so there he is...

He was an artistic polymath that -among other innovations in fashion, music, arts and aesthetics- introduced the world to the concept of three-course meals (soup, main course and dessert).

Open trade and the vastness of the empire also brought about the introduction development of new methods of agriculture, and crops; among which there are olives and citrus fruits that are currently ubiquitous in Andalucia, in specific, and Spain and Mediterranean Europe in general. Olive oil is a corner stone in Spanish/Italian cuisines, for example.

- Source: Agricultural Innovation in the Early Islamic World

EDIT: as seen above.