1. Take the pork shoulder out of the fridge and let sit at room temperature while you mix up your spices.
2. Heat your slow cooker to “SEAR” and add in the oil (If your slow cooker doesn’t have this feature, heat the oil in a large Dutch oven pot on the stove).
3. In a bowl, whisk together the chili powder, cumin, coriander, onion powder, garlic powder, cinnamon, nutmeg, cloves, kosher salt, and pepper.
4. Pat the pork dry with paper towels and then rub the spice mixture all over, massaging it into the meat. Once the pork is completely coated in the spice rub, add it to the hot pan and sear for a couple minutes on each side, or until a deep golden crust forms.
5. Once the pork has been seared on all sides, reduce the slow cooker to LOW and add in the beer, brown sugar, and BBQ sauce (alternatively, if using the stove top to brown the pork, transfer it to your slow cooker now and set it to LOW. Add in the other ingredients).
6. Cook on LOW for 8-10 hours, or until the pork is falling apart and tender.
7. Remove the pork from the drippings and increase the heat on the slow cooker to SIMMER (alternatively, transfer the drippings to a saucepan on the stove and bring to a simmer).
8. Whisk together the cold water and the cornstarch until smooth. Whisk it into the drippings and simmer for a few minutes, stirring occasionally, until it turns into a sauce-like consistency with a smooth and glossy appearance.
9. Meanwhile, shred the pork. Add it back into the sauce once it is thickened and toss to coat. Adjust the seasoning, as needed. Keep warm until you are ready to serve.

For the Sandwiches:

Warm or toast the buns and slice in half. Top with the cheese, pulled pork, pickles, and a drizzle of BBQ sauce. Serve warm.