Combine Kosher salt, Momofuku Spicy Seasoned Salt, and sugar in a small bowl.
Place pork belly on a sheet pan lined with parchment paper, then pat dry using paper towels.
Season pork belly on all sides with the seasoning mixture, and rest the pork belly fat side-up on the sheet pan.
Cover with plastic wrap and place in the refrigerator for 24 hours.
Heat oven to 285°F.
Unwrap the pork belly and transfer to a clean parchment-lined sheet pan and roast for 2½ – 3 hours, until the pork belly is tender.
Remove the pork belly from the oven, and increase the temperature to 450°F.
Cover the top of the pork belly with Momofuku Sweet & Spicy Korean BBQ Sauce, about ⅓ of a cup, then return to the oven and roast for another 30 minutes.
When it’s cool enough to handle, wrap the pork belly in plastic wrap or foil and place in the refrigerator until it’s thoroughly chilled and firm, about 6 hours.
When you’re ready to serve, heat a large skillet over medium high heat and sear the pork belly slices for about 30 seconds on each side, until they’re browned.
Build your sliders using the rolls, more Momofuku Sweet & Spicy Korean BBQ Sauce, and a quick pickle.
