First, prepare your dry rub in a small bowl, mixing together the paprika, salt, cayenne pepper and black pepper. Set aside.
Prepare your marinade, mixing together the Red Boat Fish sauce, honey, toasted sesame seed oil, apple cider vinegar, apple cider juice, and garlic.
Rub the spices all over the flank steak, and place in a glass tupperware or large ziploc to refrigerate overnight and allow to marinade. Pour the marinade all over the flank steak, and place in fridge overnight.
Place the marinaded flank steak in your slow cooker, and add 1/2 cup of water or stock. Cook on low for 8 hours or high for 4 hours.
Once done, remove the slow cooker pot and place in an oven-safe dish, and begin to shred it up-- it should happen easily! Pour approximately 1/2 liquid in the slow cooker all over the shredded steak. Serve with broccoli and cauliflower rice.