How to Make It
In a bowl, combine the 1/4 cup of salt with the sugar, juniper, white pepper, garlic, thyme and half of the cilantro. Add the pork and toss to coat. Refrigerate overnight or for up to 16 hours.
Preheat the oven to 300°. Scrape the seasonings off of the pork and transfer the meat to a large enameled cast-iron casserole. Pour the oil over the meat and bring to a simmer over moderately high heat. Cover and bake for about 2 1/2 hours, until the pork is very tender.
Light a grill. Brush the pineapple, yellow onion and tomatoes with oil and grill over moderately high heat until charred, 2 minutes per side. Cut into 1/2-inch dice; transfer to a bowl. Stir in the mint, red onion, chipotles, lime juice and the remaining cilantro; season with salt.
Lift the pork pieces from the oil. Grill over moderately high heat until charred all over. Transfer to a plate and shred the pork. Serve the pork with the salsa and tortillas.