Flour tortillas are made from a simple dough consisting of flour, water, shortening and salt, though many modern recipes also call for baking powder. Fresh flour tortillas have a silky fineness that it is impossible to mass produce, making most store-bought flour tortillas seem tough in comparison. Steaming flour tortillas returns a bit of that fresh softness, but use care to not overdo it or the tortillas can dry out or turn mushy.
Steam tortillas on your stove top by rolling a stack of six to 12 tortillas in a clean dish towel. Set the roll in a steamer tray over boiling water. Cover the pot and heat the tortillas for 1 minute. Remove the rolled tortillas from the steamer with tongs, but do not unroll the towel for 15 to 20 minutes.
Microwave-steam your flour tortillas by layering them between damp paper towels. Microwave a stack of no more than six for 45 seconds on high if you have an 1100-watt microwave and 1 minute for a less-powerful oven.
Oven-steam flour tortillas by preheating your oven to 250 degrees Fahrenheit. Roll a stack of tortillas in a clean, damp dish towel and place it in the oven for 15 to 20 minutes.
Grill-steam flour tortillas by layering them between damp paper towels and rolling them in a thick sheet of aluminum foil. Completely encase the tortillas and the paper towels in the foil so that no stray edges peek out. Place the foil roll onto a hot grill and let it sit for 15 to 20 minutes, turning it occasionally with tongs to help the tortillas heat evenly.