How to Make It
Put masa harina and salt (if using) in a bowl and slowly add 1 1/4 cups hot tap water, stirring until dough becomes a ball. Knead a few times. Shape into ten 1 3/4-in. balls and cover with plastic wrap until needed.
Line a tortilla press with 2 circles of thick plastic (cut from a resealable plastic bag). Press a ball between plastic to make a 6 1/2-in. tortilla.
Toast tortilla on a lightly oiled hot griddle or cast-iron skillet over medium heat, turning once, until speckled brown, 4 minutes. Repeat with remaining tortillas. Wrap in a kitchen towel to keep warm.