This dish is so creamy and full of flavor. I did not make polenta. I bought a log of polenta and heated it up with some milk, to reconstitute it. I spread the cooked polenta out in the bottom of the baking dish instead of cutting squares. So no layers just polenta on the bottom and the mushroom and cheese mixture on top. This was dynamite. https://www.eatingwell.com/recipe/251175/wild-mushroom-polenta-casserole/