There are a lot of different vegetable options for these, but I always use onions, bell peppers (any color, 1-2 peppers total depending on size), beans, tomato, and chipotle chile in adobo sauce, which gives them a nice smoky flavor (plus some heat!) If I have a zucchini, which I often do, I add that, and normally I'll add grated cheddar or jack cheese, but neither are required. The cheese does help the other ingredients meld together so they don't fall out of the tortilla, though; plus, cheese just plain tastes good; but if you're avoiding dairy, feel free to leave it out. Cilantro is an optional ingredient as well.
For the beans, you can use canned, but since Barry cooks dried beans for us in the crockpot, a small Tupperware container's worth works for this recipe. I'd guesstimate that this is equivalent to a typical (15.5 oz?) can of beans. Any beans will work -- black, pinto, kidney, or a blend. This is the ultimate in made-up, flexible recipe!
I use whole wheat tortillas, but you can use regular flour ones if whole wheat are not available. We usually eat two of these apiece. If you have the plate-sized tortillas typically found in the US, one per person will suffice, but the tortillas here in Belize are typically smaller. We've been buying these in large batches from Domingo's Popular Tortilla on Back Street, but I've recently seen them in Marina's and Casa Pan Dulce up on the front counter as well, if you only want a four-pack.
I had lovely fresh cilantro this time, so chopped up about 1/4 c. of it -- but I didn't add it until the very end.
Once the cheese has melted, fill half of each tortilla with a goodly amount of the bean-veggie mix, fold over, and chow down. These are meant to be eaten with the hands, but you'll probably need a fork as well to catch any fallout! Oh, and these go really well with an ice-cold Belikin (the national beer of Belize), chips, and salsa. Enjoy!