The night before or up to 2 days before cooking, pulse the anchovies, garlic, mustard, salt, sugar, pepper, and allspice in the jar of a food processor until a thick paste forms. Rub that paste all over your tied pork roast, pushing it between the cracks as much as possible. (If you care about how your hands smell, you might want to wear gloves for this process.)

If you have room to store the insert of your slow cooker in the fridge, tuck the rubbed roast into it, cover it, and refrigerate. If there’s just no room, seal it into a resealable plastic bag and then refrigerate. Let it sit at least overnight or up to 2 days so that the salt and seasonings in the paste have a chance to penetrate the meat to tenderize and flavor it.

Place the insert and the pork into your slow cooker set to low, cover, and cook until the meat is fork-tender but not completely falling apart, 7 to 7½  hours. (If it’s done cooking before you’re ready for it, simply remove it from the cooker, wrap it tightly in foil, and let it sit for up to 2 hours, then re-warm—still wrapped—in a 300°F oven before slicing.)

Transfer to a cutting board and let rest 5 to 10 minutes. Remove the butcher’s twine, then slice and transfer to a serving platter. Drizzle vinaigrette over the top, or strain some of the juice out of the slow cooker, drizzle that over the top instead, and toss a flurry of chopped herbs over the top to make it pretty.