*If you are using fish or shrimp, only let this marinade sit for 10-20 mintes. The acids in the citrus will begin to cook the proteins in the fish/shellfish, and if you leave it set longer, you will have achiote ceviche, which is arguably more lyrical, phonetically speaking, and probably delicious, just be aware of what you are doing or you will have the mushiest, mealiest, get-this-the-hell-off-my-plate-what-sort-of-sadist-are-you-to-have-served-me-this-anyway-I-thought-you-liked-me disaster that you have ever served.
**Achiote paste can be found in any Mexican market, and typically also the “ethnic” aisle of your garden-variety American megamart. Achiote is what gives cheddar cheese its searing orange color, so be careful. It stains, stains, stains.
***Pork is made of sterner stuff than fish. I’d totally put my money on a pig in a pig vs. shrimp cage match, if it came to that, though the odds would probably not equal a big pay off given the obvious physical disparities. None the less, even the mighty pig is no match for citrus if given enough time. It’s a war of attrition. So, don’t let your pig sit too long in tangy juice or you will have a pork chop so mealy it would put the worst apple to shame. See fish note.