Can you name a school that is going to allow a child to have their food fried up at lunchtime so that mom can pack the type of meal your describing? How do you pack cheese, salsa, beans etc into a lunch container for say, an elementary student and expect them to be able to put it together, without it being, oh, Soggy (If fried at home) or congealed in grease etc?
You make it at home, it lasts through the day just fine. It isn't soggy. I used to make 'em for my first (EX) husband's lunch all the time. They aren't congealed in grease either, not if you grill 'em. (ETA: Er, like a grilled cheese sandwich, a lil oil, but not a lot. You do want the tortilla to crisp.) Home made refried beans, mind. (FRESH, that you *JUST* made, then make the...I can't recall what he called 'em, but then you make the "sandwich".) The pinto beans are usually made with salt pork for seasoning.