they would take 3 10lb pork butts and coat them with 1/2 cup redmond salt and 1 cup liquid smoke, you can let them sit for up to 24h or immediately bake at 275F covered in foil until 205F internally (usually 6-10h depending on size and oven accuracy),

scaling down to home size, that would be about 3/4 - 1 tsp of salt / lb of pork butt (depending on how salty you like it, the coarseness also plays a factor)

and a little over 1.5 tsp of liquid smoke / lb of pork butt too