What kind of skillet are you using? Are you perhaps using too little oil? Canola is probably fine. I generally use sunflower oil but do not think the type of oil is the problem. Things I would experiment with is perhaps more oil in the skillet or perhaps turning the heat down a bit so that the oil does not cook as fast in the skillet.

I use a nonstick skillet and a tiny bit of vegetable oil to fry corn tortillas for tacos.

When I fry corn tortillas for tacos or tostadas I use a cast iron skillet and lard, which I render myself. It has a high smoke point, helps with the seasoning in the skillet and tastes good. I never can manage to use tongs to bend the shells, so they're usually just flat.

When I make flour tortillas for quisadillas I just use a hot cast iron pan, dry.

Annie

I don't ever use a non stick for anything that needs to get rezlly hot...I feel it degrades the surface. I use cast iron,either enameled or not and whatever oil I have handy...canola, vegetable, olive oil....

I agree with no fat at all. It's not necessary and just gives you something more to clean up.

I'm using a Cuisinart pan, not non-stick.

Ditto--no fat. Hot cast iron or carbon steel. NO non-stick ever because the high heat you need is a no-no for non stick materials...degrades the surface as already mentioned and there are concerns about fumes released from the material...lots of reports of pet birds being killed by the fumes from overheated teflon/ non-stick pans.

If the tortillas are just being heated/crisped for flat use, or rolled into a burrito, since I have gas I sometimes take metal tongs and put them right on the burner, no pan. Meh, sometimes they stick a bit, but that's no biggie. I have no idea if you can do that with electric, and nope, definitely not with induction. Otherwise I use cast iron, no oil unless frying them is the goal.

A stainless pan?

I don't use those skillets anymore because the oil always burns onto the pan and leaves that glaze, unless what I am cooking fills the entire bottom and everything is quickly and frequently stirred. Even then...................

We heat and brown tortillas all the time, but in a cast iron skillet with a lot of oil. My DD buys the parboiled tortillas that have to be cooked. We also sprinkle them with cinnamon sugar for a quick dessert.

It's the same problem with stainless steel cookie sheets. I always use parchment paper or foil.

Maybe not the flavor you want, but I use olive oil. Never had a glaze on the bottom but I do know what it is, I've gotten it from some prepacked foods.

I would alternately use coconut oil if olive wasn't an option.

Socks, I agree with cast iron. Whatever oil if you want yo fry. I usually use no oil or a very thin coating to heat up the tortilla or burrito wrapper. (I don't fry crisp, but perhaps tacos want that crispy corn tortilla.)

For removing that thin cooked oil glaze from a stainless steel pan, I spray on a bit of "Geased Lightning" and let it sit for about 5 minutes. If it still won't budge, oven cleaner will work (ventilate!). It's so much easier and _green_ to use seasoned cast iron.

What taco style are you looking for? The crispy folded shells? Corn?

We are old school and like traditional...I just heat up my cast iron stove-top griddle and lay out 4-6 white corn tortillas and lightly toast and flip a few times, no added oil, flop them into a bowl or basket lined with a clean kitchen towel, cover, then toast another batch...then to the table for all the fixin's a-la-cart.

For crisp shells you could use your oven racks. Rub a bit of oil, I use avocado oil,, and lay them on what works best for your oven...

My nephews always want the crips shells. (at my MIL's i roll a bit of foil on the rack tines, then drape...her oven is a bit filthy)

Cast Iron and peanut oil is what I use for tortillas and all my high heat frying/cooking. High smoke point, and really nice subtle taste.

Lard would be the most authentic for a true Mexican flavor, but not always that easy to find in regular markets.

If going for soft warmed tortillas, flour or corn, butter is hard to beat...

DH told me what he experienced years ago while playing football at University of Texas, El Paso as the cafeteria was mostly Mexican food. So for Taco Tuesday I fry crispy and fold using peanut oil; I use peanut oil in the salsa too.