Crispy breadcrumbs and savory Parmesan top herbed potatoes and green beans

Ligurian Potato, Green Bean and Mushroom Gratin

Name: Ligurian Potato, Green Bean and Mushroom Gratin
Cook time: 1 h 20 min
Total time: 1 h 20 min
Yield: 8 Servings
Ingredients: 4 tablespoons (½ stick) salted butter, plus 2 tablespoons salted butter, melted; 1 pound Yukon Gold potatoes, peeled and sliced ¼ inch thick; Kosher salt and ground black pepper; 3 tablespoons extra-virgin olive oil; 2 medium shallots, finely chopped; 1 pound green beans, trimmed and cut into ¼-inch pieces; 8 ounces cremini mushrooms, trimmed and sliced about ¼ inch thick; 1 tablespoon minced fresh marjoram or oregano; 2 large eggs; 3 ounces Parmesan cheese, finely grated (1½ cups), divided; ½ cup panko breadcrumbs

Appears in January-February 2021

1 hour 20 minutes 50 minutes active, plus cooling

Polpettone alla Ligure is the Italian name for this rustic, oven-baked dish. The term polpettone translates as “meatloaf,” but in this case, it refers to a mashup of vegetables baked into a casserole. In classic versions, the potatoes are cooked and pureed before cooked green beans, eggs and Parmesan cheese are mixed in. After baking, the vegetables are set enough to be cut into neat squares. For a more satisfying texture, we keep the potatoes on the chunky side, and for added savoriness, we supplement the beans with cremini mushrooms. Just before slipping the baking dish into the oven, we top the vegetables with a mixture of panko breadcrumbs and Parmesan for toasty crispness. If convenient, the gratin can be assembled, covered and refrigerated for up to six hours before baking, but keep the panko mixture separate. Just before baking, sprinkle with the topping and extend the cooking time by about 15 minutes. With a salad alongside, this dish is a satisfying vegetarian main, or offer it as a side to braises or roasts of almost any type.

8

Servings

Tip

Don’t overcook the mushrooms and beans when sautéing them, as they will continue to cook in the oven. Sauté the mushrooms until they give up their moisture and the beans are bright green but still quite crisp; they should not be browned.

1 hour 20 minutes

50 minutes active, plus cooling

Ingredients

4

tablespoons (½ stick) salted butter, plus 2 tablespoons salted butter, melted
1

pound Yukon Gold potatoes, peeled and sliced ¼ inch thick

Directions

01

Heat the oven to 400°F with a rack in the middle position. Mist a 9-by-13-inch baking dish with cooking spray and set aside. In a 12-inch skillet over medium, melt 4 tablespoons butter. Add the potatoes and ½ teaspoon salt, then stir to coat. Add ½ cup water, then distribute the potatoes evenly. Cover and cook until a skewer inserted into the potatoes meets no resistance, 15 to 20 minutes, stirring once about halfway through. Transfer the potatoes and any liquid in the pan to a large bowl, then use a fork to mash to the consistency of chunky mashed potatoes; set aside.

ligurian-potato-green-bean-mushroom-gratin

Reviews

Alkuds J.

Made this today used a couple portobello mushrooms instead of cremini. Very tasty. Family loved it ! This recipe is a keeper! Thank you!

Kevin S.

The recipe could have easily included: slice the potatoes and the mushrooms with the slicing blade of a food processor. Mash the potatoes with a potato masher (which is, y'know, MADE FOR MASHING POTATOES - a fork is usually used for serving or eating). And finally - it would have been kind to indicate cutting 1 lb of green beans into 1/4" pieces is again, a task best done with the chopping blade of a food processor.

Sandra R.

You are right about a using a food processor but I did it by hand and it wasn't that time consuming. Like you, I also use a potato masher.

Sona E.

Some people, me included, don't have a food processor.

Barbara W.

I neglected to cut the string beans and in no way did the casserole suffer. Once baked, the string beans cut easily with the side of a fork.

Barbara W.

I just test drove this recipe in preparation for Thanksgiving. It was great. I made a different topping since I don't like cheese in Thanksgiving dishes. I have been looking for an alternative green bean casserole without Campbell's and this is it. I will be making this again in 3 days for the big day. Thank you.

Josh O.

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Cass and DJ L.

This recipe is delicious and went amazingly well with ribeye steaks.

Sandra R.

This was terrific. Really enjoyed it. Definitely a keeper. We had it with grilled turkey breasts. I think this would be a great side dish at Thanksgiving.

Laura B.

This is mind-blowing! Even my 22-month-old daughter loved it! I agree with Sandra R. about this being a great side dish for Thanksgiving. This is like a 3-star Michelin dish-version of green bean casserole. What amazing combination of ingredients, as it is just so savory! My husband is a fan, and he said this recipe is a keeper. I made quick work of the green beans and mushrooms by having them sliced in my food processor, same with the potatoes, too. Everything just came together as a perfect homogenous mixture. I had to take it out of the oven around the 20ish minute mark, as it was starting to bubble already, so make sure to check on it at about that time frame.

Jennifer B.

Really delicious. Great combo of vegetables.

Tatiana R.

So with the shortages of random things, it was hard to find decent green beans. We bought a single bag of pre-trimmed ones (still had to trim them again because they didn't look so hot) that was only 12oz, rather than a pound. Also, got half a pound of mild Italian sausage because my son really doesn't like mushrooms. I split the beans and the shallots in two batches so I could make half of them with mushrooms and half with the sausage. I just had the left side of the baking dish filled with the mushroom-based mix and the right side with the sausage-based one. As you can see, with less beans and with 8oz of mushrooms AND 8oz of sausage, it's a different proportion of ingredients than in the recipe, but it all still looked right and tasted good. I wish there were more potatoes.

Merilee L.

Has anyone tried making this with mashed cauliflower instead of potatoes?

Linda W.

Pretty bland as written. Significantly better with triple the marjoram and addition of some Cajun seasoning.

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Ligurian Potato, Green Bean and Mushroom Gratin