I usually add a layer of frozen corn, then a generous layer of tator tots.
In a mixing bowl, stir together 1 can evaporated milk, 1 can cream of chicken, 1 can cream of mushroom (or substitute for another "cream of" for you mushroom-hatin' Oshels).
Pour the soup mixture over the TOP of the casserole. This is the trick I picked up recently. Before I used to put the tots on top and it wasn't nearly as good.