So, the chorizo in this recipe sounds like maybe it's a Spanish chorizo, right? Not Mexican (the only type I have any experience with)?

So here's a thing about chorizo. The term refers to a type sausage in just about every Spanish-speaking country. Spanish chorizo typically refers to chorizo cantimpalo, which is a dried, cured sausage that doesn't require cooking. These fresh chorizo sausages that the recipe describes can be Mexican chorizo in its casing (the type in tacos is typically loose sausage filling). It can also be Argentine or Colombian chorizo. Argentine or Colombian chorizo is milder and probably goes better with the other ingredients in this panini. Mexican chorizo may be too assertive and overpower everything else. I hope this helps