On a large plate, combine oregano, cumin, salt, chili powder, onion and garlic powder. Mix well. Place the pork on the plate and rub all the seasoning into the pork.
Get out your slower cooker. Add the onion, jalapeno, garlic cloves, and lime & orange juice to the slow cooker. Top with the seasoned pork.
Cook on low for 4 - 6 hours or until shreds easily.
Shred the pork, using two forks.
<Optional Step> Spread the shredded pork out on a baking sheet. Broil for 5 - 7 minutes or until the ends get slightly browned and crispy. Remove from oven and stir in fresh, chopped cilantro before serving.
Use pork in tacos, bowls, or salads.