Back in the Fifties, Campbell's cream of mushroom soup was a kitchen staple as a shortcut for folks unwilling to make a cream/white sauce. You couldn't hardly make a casserole without it. My mother used it (to good effect, I have to say) in her signature scalloped potatoes. And back in high school, I made it on several occasions to take to John's house when the family was having a cookout. Everyone loved it.
But I've been determined to reproduce the great flavor without the mushroom soup and the canned mushrooms. At last I can cry Success! (We had it with barbecued chicken, kind of a perfect pairing.)
Scalloped Potatoes w mushrooms and cheese for 6
12 (more or less) red potatoes sliced thinnish (¼ inch)
2-3 onions sliced
Mushrooms—1 cup or more. Sliced
Butter, salt and pepper, oregano, garlic granules
3 c milk (or ½ and ½ diluted)
Grated parmesan and Havarti (or mozzarella) -- about 2 cups
Saute onions and mushrooms in butter. Remove.
Make cream sauce with 4 TB butter and 3TB flour—add 3 cups milk (or diluted half and half. ) Cook till thickened, Season w salt and pepper and garlic granules
In buttered casserole, make a layer of potato slices, top with sauteed onions and mushrooms. Cover with 2/3 of cheeses and sprinkle heavily with dried oregano. Pour on half the cream sauce. Cover with the rest of the potatoes. Pour on remaining cream sauce. Add remaining cheese.
IF the potatoes are not covered with the sauce, add heavy cream.
Bake at 350 about an hour and a half.