-You may use either corn or flour tortillas. When using flour tortillas, I use standard size tortillas (not burrito size) and I look for tortillas that are not the thick variety. I like the look of yellow instead of white corn tortillas, and most of the time prefer corn tortillas in this recipe. The cron tortillas will tear a bit if not softened first. I have found heating the tortillas in a damp paper towel in the microwave for a minute softens the tortillas a bit, but is not worth the extra step and time since the tortillas are eventually covered in cheese and sauce. -If using corn tortillas, lay the rolled and filled tortillas in two rows of 5. For flour tortillas, lay the tortillas in one long row of 8. -This recipe works well with either red or green enchilada sauce. I look for a brand that does not include MSG. Look for the word "enchilada" sauce and not just red chile sauce or green sauce. -The addition of sour cream will make the sauce not quite as vibrant, but will also add a creamier texture to the sauce. It will also cut some of the spiciness of the red enchilada sauce. I am not a big fan of spicy foods. the recipe as written with 1 teaspoon of chili powder and the Red Chile Enchilada Sauce has just a bit of spice. If you are serving this to young children, leave the chili powder our of the filling.-If you are in a hurry and want to make this casserole style, cut the tortillas into 1-2 inch strips, place a layer of sauce on bottom of pan as directed. Layer tortillas, filling and cheese. Then add one additional layer on top of the first layer and end with pouring the sauce evenly over the entire casserole. Bake as directed.