Cut the pork into thin slices measuring about 4-inches square; smaller pieces are fine.
Stir the brown sugar, seasoned salt, garlic salt, pepper, and curing salt together in a bowl; sprinkle each of the slices of pork with the mixture. Lay the pork slices flat in a large container with a cover. Let sit in the refrigerator 3 to 4 days before using.
To prepare the tocino, combine the desired amount of the pork with enough water to cover in a large non-stick skillet and bring to a boil for about 5 minutes. Drain and discard the water. Dry the pan completely.
Heat the oil in the skillet over medium heat; fry the pork slices in the hot oil until lightly browned, 1 to 2 minutes per side.