I've not made them but was told by one Mexican lady that if the tortillias are to thich, your starting with too big of dough ball. That being said I did buy some masa a couple of weeks ago and when I get a little extra time I'll give it a go too! Good question though!

Have you tried plastic wrap on your press?

I use a one gallon zip loc bag that I cut the top and sides off.  Put the dough in the plastic and mash down as hard as I can with the bottom of a skillet and then work them down thinner with a rolling pin.

You peel the plastic off the tortilla, as opposed to peeling the tortilla off the plastic if that makes sense.

Look at gothicgirl on March 13, 2009 here in TFL under flour tortillas and you'll find some help. I too have trouble forming tortillas -- the thickness does make a difference! 

Well, I'm no expert on this but I know the basics enough to start you off.

First, there are flour tortillas and corn tortillas. The flour ones are what you are asking about. The  Masa is corn flour that has been treated with lyme. The corn tortilla is the one that is pressed to get a perfect circle.

The flour tortilla is made from a ball of dough, a little larger than a golf ball, say 1-1/2 inches. Here is the recipe.

2 cups all-purpose flour
1/4 cup lard, or vegetable shortening
1/2 teaspoon salt
1/2 teaspoon baking powder
3/4 cup warm milk, or water
Combine the dry ingredients in a bowl. Transfer to the bowl of a stand mixer.
Add the lard and mix until it is well combined and the mixture looks grainy.
Add the warm milk and mix until a smooth ball of dough forms, about 5 minutes.

Divide the dough into 12 equal pieces and roll the pieces into balls.
Cover and let rest 30 minutes.
Once rested, roll the balls of dough into 6″ to 7″ tortillas.
Cook on a griddle, or in a heavy pan, over medium heat until golden brown and puffy.
Transfer to a plate and cover with a towel while the rest cook.
Enjoy!  Or, allow them to cool and store them in a plastic bag in the fridge.  They last for five days ... if you can keep from eating them hot off the griddle.

The corn tortilla made from Masa Harina or other treated corn flour is tastier in my opinion and the recipe is on the bag of flour. These are the only ones that get pressed. Start off cutting a 1 gallon freezer bag in half and making 2 circles out of the sides of the bag a little larger than the plates on the press. Lat one piece down then the dough ball slightly off center toward the hinge, then the top sheet of plastic and press gently. Remove the top plastic first and flop the lower sheet over on your hand and carefully peel the plastic sheet off. Then gently flop the pressed dough onto a hot griddle. The trick is in knowing how much water to add the flour. If you press the ball and the edges are rough around the edges, it needs a small amount of additional water. If the dough is hard to remove from the plastic sheet and tears when doing so, it is too wet, add a little flour. Hope this helps.

Eric

We don't need no stinking bag-ses. There is a joke in there somewhere.

I make tortillas frequently, What you need it a good rolling pin and a large counter top.

Just dust with a bit of flour and roll. Keep flipping them over and dusting with flour to keep them from sticking. There really is no trick. If you want them thinner, roll them thinner. It takes practice to get them round but you will get the hang of it.

As for moving them to the griddle, use the bottom of a large upturned bowl, Or drape over your fist.

P.S. Lard is the way to go here.

I use the instant masa flour myself which you just add warm water to. I just add a couple drops more water and let rest. To flatten I lay a sheet of waxed paper on the counter and place a small ball of dough on it and flatten slightly by hand. Place another sheet of waxed paper over it and useing a pyrex pie plate push down and tip and tilt it as you push, it works great for me

I use a pasta machine to shape my tortillas.  Works quite well, although getting a perfect circle is a challenge.

If you live in a dry climate, the flour might have dried out on the store shelf. Try adding a little water.

I used to have a devil of a time, but now adding more water, it flattens right out for me.

I always make flour tortillas.  I don't have my recipe on this computer, but I mix King Arthur bread flour and home milled white whole wheat, some salt and baking powder and warm milk and olive oil.  It's not an authentic recipe, but it tastes pretty good.

I think the key to rolling them out is to use a piece of dowel about an inch thick and about 18 inches long.  Roll them, then flip them over and give it a half turn, roll them again, keep doing that until they are thin and round-ish.  I cook them about 30 seconds on each side in a hot cast iron skillet.

Softer dough rolls out thinner, but you need to heavily flour your surface and turn the rounds over as you roll out, and keep your rolling surfaces on both sides of the dough well-floured.  I use this technique when rolling out thin Asian pancakes and wonton wrappers, etc. 

Another method, which you won't need if you start with the soft sticky dough, is to double the rounds.  I use this when making very thin wrappers for "mushu pork":  Make your dough balls and roll them out til they are fairly thin.  Then brush one side  of half the rounds with oil and place a second rolled out round on top.  Now roll the doubled-up rounds out as thin as the single rounds (which should halve the thickness of each pancake.  When you place them on the hot skillet, they will puff up and the rounds will easily separate, and you can fry them separately.  I would only do this if you are using a fairly stiff dough and rolling them out very thin.  This results in a very thin bread, probably thinner than you want for tortillas, but it works.

I don't use lard because the idea if it weirds me out.  I use shortening.  Which should also make me feel uncomfortable.  The recipe that Eric posted is good.  However, I use hot water, around 130 degrees.  The hot water helps to soften the shortening.  Also, here is the real hint, flatten your golf-ball sized ball out with the palm of your hand first.  After it has been flattening as much as it can go before snapping back, let it rest under saran wrap for 5-10 min.  This allows the gluten to relax.  Once you have let it sit you should be able to use a rolling pin and roll it paper thinness.  I have been making my own tortillas for a while now and I refuse to buy store bought ones. 

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