Holy Spit is where the Mr. Popo's line stops being polite. It is genuinely hot, and pork shoulder is the right place for it because there is enough fat and enough sweetness in the meat to carry the heat without the sandwich becoming a dare.

Pull along the grain, not across it, and stop while the shreds are still long. Shredded pork that has been worked into mush has no texture left, and once you add sauce it turns into wet stuffing. Long strands hold their shape in the bun and they hold sauce in the gaps instead of soaking it up.

Sauce the pork while it is still warm, not cold out of the fridge, and use less than you think. Then the slaw does the real work. Vinegar, no mayo, cut fine. It is not a garnish here. It is the thing standing between Holy Spit and your palate.