Make Ahead Green Bean Casserole

LeoChic

I'm making the traditional Campbell's version of green bean casserole because DH (and his family) loves it.  Can I go ahead and mix all the ingredients together (minus the onion topping), throw it in a casserole dish in the fridge and then just warm it tomorrow?  I'm afraid it will get mushy.  I'm using frozen french style green beans if that makes a difference.

Zenya

I would want to risk it getting any more gross than it normall is.  Not like it saves all that much time anyway right?  What is it just milk and soup?