The thing about enchilada casserole is...
that once you have the "base" recipe done, you can add/subtract anything you want

And

It still tastes good.

I added one small can of green chilies to this recipe.
I didn't have refined beans, but I did have black beans! and it still turned out delicious.
I think you can easily double the ingredients and make it in a 9x13 for a crowd. But a 8x8 was perfect for the two of us...by the time we polished it off, we were sick of eating it.

I've made A LOT of enchilada casseroles, but found the recipe mentioned above to the "one." But I do want to mention that you never really want to boil chicken, but almost to the point of boiling...the chicken can/will get chewy if boiled.