I am suddenly very very hungry......

Adding THC to this should be pretty easy, there is some fat in with the pork for it to bind too, and the alcohol in the beer is also a possible carrier/disperser of THC, but it will evaporate pretty quickly.... You might just toss a few good sized fresh or dried buds into the crockpot along with the rest of the ingredients, but this method would tend to add more flavor than effect. If you could add a little cannabis infused fat (butter, olive oil, coconut oil) to the cooking recipie would be better for effect, but harder to homogenize into this kind of mixture.

I think maybe making a nice guacamole with the avacado that includes some infused olive oil mixed in for the taco garnishing may be the better way to get the kick into this dinner. I might even throw a small amount of fresh frosty trim in with that cilantro, but that's just me. I have been known to enjoy some small buds in a nice salad occasionally.

I'm a little nuts.... I might do all of that.... but many people find the effects of orally consumed cannabis to be:
A) slow to come on
B) very strong once in effect
This can easily lead to taking more than is comfortable for some, so untill you have tested any of the methods I have suggested, its better to go low and slow untill you get a feel for cannabis edibles, and a particular recipie. This makes it harder to do a whole dinner (unless the goal is everyone sleeping, lol) but a cannabisized side condiment may be easier to control. (Or hide.. Brought yer own guacamole to the party huh? Nice tacos baby.)

Nice recipie, and thanks for sharing.
YBG