I made the beef enchilada casserole last night (29 minutes to dinner). I could not find yellow corn tortillas at the grocery store, so I got the white corn tortillas. In chef's corner, it says this is an ok substitution. I would NOT recommend using them. The yellow tortillas are crunchy, the white ones I found are softer. Not as soft as flour tortillas, but soft enough that the casserole turned to mush. Has anyone else had that happen?