- Mix dough. If using powdered masa harina, measure into bowl and add 1 cup plus 2 tablespoons hot tap water. Mix with hand, kneading until thoroughly combined. Cover and let stand 15 minutes. If using fresh masa, scoop into bowl. Break up and knead a few times until smooth.
- Heat griddle or skillets. Set large griddle (one that stretches of 2 burners) or 2 skillets on stovetop. Set heat under one end of griddle (or one skillet) at medium. Set heat under other end (or other skillet) at medium-high.
- Adjust consistency of dough. Gently squeeze dough. If it is stiff (it probably will be), knead in water 1 or 2 teaspoons at a time until the dough feels like soft cookie dough—not stiff, but not sticky. Divide evenly into 15 pieces and roll each into a ball. Cover with plastic.
- Press out dough balls. Cut 2 pieces of plastic bag 1-inch larger than tortilla press. Open press. Lay in one piece of plastic. Lay dough ball in center. Gently mash. Top with second piece of plastic. Close press. Press gently—enough to mash dough into 1/8-inch disc. Pull off top piece of plastic.
- Unmold uncooked tortilla. Flip tortilla onto right hand (if right-handed). IMPORTANT: top of tortilla should line up with top of index finger. Lay on medium-hot griddle (or skillet) by letting bottom of tortilla touch griddle, then lowering your hand slightly and moving it away from you—the tortilla will stick to the hot surface so you can roll your hand out from under it as it rolls down flat.
- First flip. After about 30 seconds, edges of tortilla will dry slightly and tortilla will release from griddle—before this moment, tortilla will be stuck. With metal spatula (or callused fingers), flip onto hotter side of griddle (or hotter skillet).
- Second flip. After about 30 seconds, tortilla should be browned underneath. Flip. Cook 30 seconds more—tortilla should puff in places (or all over—a gentle press with metal spatula or fingers encourages puffing). Transfer to basket lined with towel.
- Continue. Press and bake remaining tortillas. Stack each baked tortilla on previous one. Keep tortillas well wrapped in towel to keep warm.