I've never seen a mold that would shape them - any tips?
This is an art. Anyone who appreciates REAL tacos, can understand that this is not easy. God Bless anybody that can pull this off accurately!
I have it down to a science. I learned from my grandfather. His biggest secret was in the fork you use. We use cooking forks. 3 prong cooking forks (most of the ones I see on google have two prongs). You can use regular forks too, but they arent made for cooking in high temp oil.
First you must get the oil HOT. 350 atleast, preferably 400 degrees. Just before it starts smoking. You need really high oil heat.
Once the oil is PLENTY hot, you hold a tortilla in one hand, and drop it in the oil halfway. It should be at 90 degrees, with your hand still holding the dry half of the tortilla. (Note: keep your cooking fork ready for the next steps)
If your oil is hot enough, it will cook that half of the tortilla almost instantly. Let it cook until it hardens up, which should be less than a minute.
Once the first half the bent tortilla is crisp, use the cooking fork to grab the tortilla half that is crisp and cooked. You will flip it here, putting the dry tortilla half (that was in your hand) into the oil, while the cooked half, sits above the oil with your fork. Now it should cook the other half of the taco shell.
The art is using the fork well enough to create a gap at the base of the shell (for meat or whatever you stuff with). And then flipping it and holding it with the fork while the other side crispens and finishes up.
I would like to make a youtube video that shows this process, and it truly is an artform. Many people make great tacos but horrible tortilla shells. I grew up near Mexico, I was born 4 miles from Matamoros. I have seen my share of taco cooking, in the strangest of places. The best tacos Ive ever had use this method. And the best taco makers Ive ever seen wouldnt do this any other way (by hand).
It's hard to do this without burning your hand(s). Be careful. The dry tortilla absorbs the hot oil, even when your holding it over the grease in the first step. Youd be surprised how a corn tortilla will drink the oil right up to your hand.
Give it practice. You will mess up a few tortillas. Dont worry about that, they make great quesadillas or nachos :)
No mold required!
Simply heat about an inch of oil in a frying pan (less oil if you're making less shells - this is enough for about a dozen), then cook small, flat corn tortillas one at a time.
Cook for about 15 seconds on each side. Once you see bubbles on the tortilla, you're all done if you like soft shells.
If you like more crispy shells, go ahead and fold the tortilla in half, and continue to cook. Keep flipping it over so you don't get it too browned on either side.
You can blot the tortilla with paper towels if you'd like.
Similar topic - you can make your own shell for taco salad by placing a large flour (burrito-size) tortilla in an oven-safe bowl (shaped however you'd like) and putting a big ball of tinfoil inside it. You can also do the opposite - place the bowl upside-down and drape the tortilla over it. Either way, Bake at 350 degrees for 10-15 minutes until it's lightly browned, and you're done! When you remove the tinfoil and the bowl, the tortilla will hold its own shape.
I've seen Alton Brown make one out of a large piece of tin foil, folded over several times and molded into a taco shape. See pictures at the bottom of this article: http://www.ourbestbites.com/2010/07/beef-tacos-plus-make-your-own-taco.html
(I haven't actually tried this myself)