Easy Does It Casserole

This recipe is from my grandma's recipe box.  :)
There is no mention as to where this recipe originated from.

Brown together 1 pound hamburger and 1 chopped onion.  Add 2 cans chicken rice soup and 6 cups Rice Krispies, add mushrooms if desired.  Mix all together and place in casserole dish.  Top with crushed potato chips.
Bake at 350 degrees F. for 45-60 minutes.

*Cooks note.  I used a 9x13 to bake it in.