Homemade Corn Tortillas

1 cup masa harina (found in the Latin food section of the grocery store)
2/3 cups plus 1 tablespoon water
pinch of salt

Put masa harina in mixing bowl and make a well in the center.  Pour water into the well and stir to form a dough.  Knead the dough until it's soft but not sticky (should feel like play-doh).  Pinch off a palm-size piece and roll into a ball.  Cut out two 7" circles from cleaned plastic grocery bags.  Put 1 circle on a tortilla press, place dough ball in the center and top with second circle.  Push handle down on tortilla press to flatten the dough.  To make it thinner, wiggle the handle from side to side while pressing down.  Open the press, remove the top piece of plastic and transfer the tortilla to the palm of your hand, pulling off the second piece of plastic.  Cook the tortilla in a heated cast-iron skillet over medium heat.  Make sure it's lightly toasted on both sides.