Request Please - Crab/potato/onion/cheese brunch (?) dish

I am looking for the recipe for a dish that was on the breakfast menu at the old “Piano Factory Restaurant” in Grand Haven, Michigan in the 1980’s. They called it the “Bus 30 Special”. It was a combination of crab chunks, potato chunks, onion, possibly ham, possibly mushrooms. NO eggs. NO cream. It appeared that the potatoes & onions were fried up, then the other ingredients added, with the cheese put on last. Possibly put in oven for a short time? I have no idea of the seasonings that were used.

It was very good. Thank you for any help you can offer.