Begin by roasting the jalapeños, either on the grill or under the broiler in the oven.
Once the skin on the jalapeños is black and bubbling, remove from the heat and place in a plastic bag, zip closed and set aside for 5-10 minutes.
Remove from the bag and peel the skin from the jalapeños.
De-stem and seed the jalapeños, then place in a blender or food processor with the blackberries, garlic cloves, olive oil, apple cider vinegar, honey, lime juice and cilantro, blend until smooth.
Combine the cumin, paprika, kosher salt and black pepper in a small bowl.
Rub this mixture on the pork and place in the crock pot.
Pour the roasted jalapeño blackberry sauce from the blender onto the pork.
Cook on high for 3-4 hours, or on low for 6-8 hours.
Use a couple of forks to shred the pork in the crock pot.