Heat olive oil in a skillet over medium-high heat. Brown pork cubes on all sides and transfer to the slow cooker.
In the same skillet, sauté onion and garlic for 2-3 minutes until fragrant. Transfer to the slow cooker.
Add chopped tomatillos, jalapenos, chicken broth, cumin, oregano, salt, and black pepper to the slow cooker. Stir to combine.
Cover and cook on low for 6-7 hours or on high for 3-4 hours until pork is tender.
Use a fork to shred the pork slightly, mixing it with the sauce.
Stir in chopped fresh cilantro just before serving.