Up until I made this, summer squash was one of the three foods I did not like. Now, at least in potato gratin form, I think it's delicious. So, even if you don't like squash, give this recipe a try. It made eating a potato gratin actually feel healthy (regardless of whether or not that's true). It's also really beautiful.
a mix of potatoes-- I used 2 purple potatoes & 8 small Russian Butterballs. Yukon Gold would work as well.
2 large crookneck squash
1t olive oil
1/4c heavy cream
some hard cheese (I used Gran Padano; Parmesan or Pecorino would work too)
salt & pepper
Preheat oven to 350 degrees.
Peel potatoes if desired. Slice very very thinly with a mandoline or food processor (fitted with a slicing blade). Slice squash as well.
Grease a baking dish and toss squash and potato slices on to form a bottom layer. Salt and pepper; dot with butter; grate some cheese on top. Repeat, making at least 2 more layers. Dot top layer with butter and put extra cheese. Pour cream on top.
Cover with aluminum foil and bake for 30-40 minutes. Remove foil and bake until potatoes are tender, liquid has evaporated, and top is golden brown, about 20 minutes.