To puff tortillas, especially if they are made from masa dough, you need to fry them. Heat oil in a deep fryer or a deep pan to a medium-high temperature. Gently place the rolled-out masa or tortilla into the hot oil. The tortilla will begin to puff up almost immediately. Use tongs to carefully turn the tortilla over to ensure even puffing and browning on both sides. Once puffed and golden, remove it from the oil and let it drain on a paper towel.