The only complicated part is slicing the vegetables paper thin. We love our mandoline for this (they're not expensive, and we highly recommend one for so many dishes), but if you don't have one, you'll just need a bit more time and a very sharp knife.
There's not a ton of cheese and no cream (just a splash of milk to keep it tender), so the fresh taste of the vegetables is front and center. We sprinkled our gratin with basil at the end for a little color. It was a near-perfect dinner (and great leftover, FYI).
This classic and simple recipe from Elizabeth has always received rave reviews from our readers and commenters, and I finally had a chance to try it last week. I was shocked by how quickly it came together. I sliced up the squash and potatoes on my mandoline, just as Elizabeth advises, and jumbled them higgledy-piggledy in a casserole dish. When baked, they were tender and soft, but they still tasted vibrant and fresh — unlike vegetables in gratins that are swimming in cheese and cream. This was a keeper. I can hardly wait to make it again. - Faith
Potato, Squash, & Goat Cheese Gratinserves six
2 medium yellow squash, about 1/2 pound
4 small to medium red potatoes, about 1 pound
3 tablespoons olive oil
4 ounces goat cheese
Salt and freshly ground black pepper
1/4 cup whole milk
1/3 cup freshly grated Parmesan cheese
1 tablespoon thinly sliced basil or thyme leaves
Preheat oven to 400°F. Lightly grease a 1 1/2 to 2-quart casserole dish with a drizzle of olive oil.
Use a mandoline or chef's knife to slice the squash and potatoes into very, very thin slices, 1/8-inch or less. Toss the sliced vegetables with the 3 tablespoons olive oil in a large bowl.
Place 1/3 of the squash and potato slices in the bottom of the dish — no need to layer them squash-potato-squash; just spread evenly — then season with salt and pepper. Top with half of the goat cheese, scattered evenly in large chunks. Repeat with another 1/3 of the vegetables, seasoning again with salt and pepper and topping with the other 1/2 of the goat cheese. Finish by layering on the final 1/3 of the vegetables and seasoning with salt and pepper.
Pour the milk over the entire dish. Top with the parmesan cheese. Bake, covered, for 30 minutes, then uncover and bake 15 more minutes, until the top browns. Scatter on the fresh basil, if using.
Related: Recipe: Kale and Potato Gratin
(Originally published July 21, 2009)