In your slow cooker, combine the cut up pork butt, onion, orange, chicken stock, lime juice, cumin, oregano, salt and pepper. Stir to combine and cover. Cook over low for 6-8 hours, or high for 4-6 hours.

Gently remove the cooked pork butt from the slow cooker, it is going to be very tender. Transfer it to a plate, and break each chunk in half with a fork.

Strain the cooking liquid from the slow cooker. Discard the solids. Allow the cooking liquid to sit for 5 minutes, then spoon the fat off the top. Boil the cooking liquid over high heat until it is reduced by half to 1 cup.

While the cooking liquid is reducing, turn your broiler on High with the oven rack in the middle. Line a rimmed baking sheet with parchment paper.

In a medium size mixing bowl, add the carnita meat and toss with the reduced cooking liquid. Transfer the meat to the parchment lined baking sheet.

Broil for 10-15 minutes until the meat is crispy. No need to turn it. Remove it from the oven and allow it to cool a minute or two.

Serve the carnita meat in the taco tortillas topped with chopped onion and cilantro and a squeeze of lime juice.