In a small bowl, combine the chili powder, oregano, garlic powder, paprika, cumin, salt, onion powder and espelette pepper. Rub the spice mixture generously over the roast.
Place the roast in a slow cooker fat side up. Pour the lime juice and water over it and cook it on low for 10-11 hours.
An hour before you plan to eat, wash and dry the potatoes.
Preheat the oven to 425°F.
Place the potatoes on a baking sheet and poke holes in each side with a fork. Drizzle with the olive oil, rubbing to coat each fully, and sprinkle with the salt.
Bake the potatoes for 50-60 minutes, flipping 2-3 times. Potatoes are done when a knife pierces the skin easily and the potato is soft.
When the roast is ready, remove and discard the fat cap from the top. Using tongs or forks, gently shred the pork into bite size pieces. Toss with the juices and keep warm.
Slice just the top of each potato and press in the ends so that it opens as if it were a hot dog bun. Spread the butter on each potato and top with the cheese, pulled pork, pico de gallo, prepared Jalapeno Ranch and sour cream.