Step 1

Slice the pork shoulder in half lengthwise. Cut each piece across into thin, 1/8-inch slices.

Step 2

Transfer pork to a mixing bowl and add garlic, onion, brown sugar, salt, pepper, paprika, cumin, and cayenne. Mix with your hands until thoroughly combined.

Step 3

Wrap in plastic wrap and transfer into a refrigerator for 4 hours, or up to overnight.

Step 4

Preheat an charcoal grill for medium-high heat and lightly oil the grate.

Step 5

Weave pork slices on metal skewers, folding the longer pieces in half as you go. Slices should be pressed snugly together as you build the skewer.

Step 6

Grill skewers over the hot charcoal until browned and no longer pink, turning frequently, about 30 minutes. Brush on barbecue sauce and turn skewers several times so the sauce caramelizes, about 10 minutes more. An instant-read thermometer inserted into the center should read at least 160 degrees F (71 degrees C). Serve immediately.