Cremini Mushroom And Zucchini Gratin are the easiest and the most elegant looking appetizers to serve to your guests. Everyone gets their own individual dish. That always seems to make friends and family feel extra special.
Whenever I make a tomato sauce, I always seem to have plenty left over. There’s just two of us so I’m always trying to think up different ways to use any leftover sauce. That’s how this dish came to be. This recipe can be made easy enough even if you don’t have leftover sauce, use your favorite jarred marinara sauce.
Prep Time: 25 minutes, (includes slicing and sautèeing of the vegetables)
Cook Time: 30 minutes
Total Time: 55 minutes
Yields: 4 servings
Equipment: 4 gratin dishes, 2 rimmed sheet pans, 1 (12-inch) sauté pan, mini food processor
1/2 cup olive oil, divided, plus 1 tablespoon
2 tablespoons of butter, unsalted
2 zucchini, 1/4-inch slices
1 yellow squash, 1/4-inch slices
2 pints of cremini mushrooms, sliced (small ones quartered)
1 1/2 cups leftover Homemade Marinara Sauce, (substitute your favorite jarred marinara sauce)
2 tablespoons of fresh thyme leaves (or 1 tablespoon dried thyme)
1 tablespoon Kosher salt (for seasoning zucchini and squash)
1 teaspoon freshly ground black pepper (for seasoning zucchini and squash
1/4 cup Ricotta cheese, whole milk
1/4 cup half-and-half
1 large egg
3/4 cup plus 3 tablespoons of Parmigiano-Reggiano cheese, freshly grated (reserve 3 tablespoons for the top of each gratin)
1/4 cup of Italian flat-leaf Italian parsley, finely chopped (reserve 2 tablespoons for garnish)
Preheat oven to 400-degrees F.
In a large sautépan over medium-high heat, carefully melt the butter with the 1 tablespoon of olive oil. Add the sliced mushrooms and fresh thyme leaves.
Sautè the mushrooms, about 5 to 7 minutes, or until they’re brown and tender. Only then season with Kosher salt and freshly ground black pepper to taste. Transfer to a plate lined with a paper towel.
Note: Wait to salt the mushrooms until they browned completely. This process allows them to brown and not steam from the water they release.
Slice 2 zucchinis and 1 yellow squash about 1/2 an inch thick. Place them into a bowl and sprinkle with Kosher salt and freshly ground black pepper. Using the same sautè pan, over medium heat, add 1/4 cup of olive oil. Give the oil a chance to get hot but not where it’s smoking.
Arrange the sliced zucchini and squash in one layer in the pan, do not overcrowd the veggies. This needs to be done in two separate batches. They will shallow fry for about 2 minutes per side. Do this just long enough for the veggies to soften and get some nice color on them before they go into the gratin dishes. Repeat the process for the remaining zucchini and squash using the remaining 1/4 cup of olive oil.
Again, have another large plate lined with a paper towel ready for the sautéed veggies once they’re finished cooking to drain off any extra grease.
While that’s working, go ahead and process the Parmigiano-Reggiano cheese in a food processor. Transfer to a bowl and set aside.
In a large bowl add the ricotta, egg, half-and-half, Italian parsley, 3/4 cup of the grated Parmigiano-Reggiano, and a pinch each of Kosher salt and black pepper, mix to combine. If you are using leftover marinara or are using jarred, have it ready.
In each of the 4 gratin dishes, place a layer of the zucchini and squash. Next, and a thin layer of the marinara sauce. To that, add the sautèed mushrooms. Sprinkle a little of the reserved grated cheese on top of the mushrooms. Next spoon on a third of the ricotta cheese mixture.
Finally, top each gratin with a tablespoon of the grated Parmigiano-Reggiano cheese. Place the dishes on a rimmed sheet pan. Bake for 30 minutes. Finish by garnishing with finely chopped Italian flat-leaf parsley. Serve hot.
There you have it, my Cremini Mushroom And Zucchini Gratin.