Plase salt, pepper & curing salt in a mixing bowl and mix well with fingers. Add sugar - breaking up any lumps
Place belly on a rimmed baking sheet. Rub half of cure into the top, flip - use rest of cure.
Put belly and any remaning cure in a large plastic bag. Remove air - seal bag, put in foil pan or roast pan to contain leaks
Cure for 6 days - flip each day - liquid will accumulate in bag - don't freak
Drain and rinse well with cold water - blot dry w/ paper towels
put on wire rim rack over baking sheet to dry in fridge overnight you might be tempted to salt this again - don't it will come out super salty however adding cracked black pepper and any other spices here might be a good idea
put on heated smoker (~170F) smoke until internal temp hits 155F (3.5-4 hours)
put on wire rim rack over baking sheet to cool to room temp
Wrap in butcher's paper or plastic wrap 4 hours to overnight
Keeps for 5 days in fridge or frozen for months
Notes: Pork belly can be bought at Whole Foods - but usually comes in 10-12lbs - ask them to remove the skin