For the Flour Dredge: In a medium bowl, whisk together seasoning salt, flour, black pepper, white pepper, cumin, curry powder, paprika, MSG, and cayenne.
Fit a wire rack over a rimmed baking sheet. Working with one piece of chicken at a time, lift chicken from brine and dip in the flour mixture to completely coat, using fingers to press the flour coating onto every nook and cranny.
Special equipment
Two wire racks and rimmed baking sheets; large cast iron skillet
Make-Ahead and Storage
The chicken is best eaten right after making.
Place about 1 heaping tablespoon refried beans into the bottom of the “bowl,” then top with about 1 heaping tablespoon shredded cheese. Using moist fingers, carefully bring dough edge together, enclosing the filling within, and press to seal. Roll the ball in your hands to return it to a uniform ball shape. Carefully pat pupusa down into a flat round about 4 inches wide and about 3/4 inch thick; if edges crack, run a wet finger around them to smooth them. Place pupusas on a baking sheet and keep covered with a towel as you work. Repeat with remaining masa balls and fillings.
