Easter Traditions – Potato & Mushroom Au Gratin

There are three things I vividly remember about celebrating Easter as a child: wearing frilly Easter dresses to go to church in with my sisters & parents, the Easter egg hunt at St. Rocco’s (it was awesome!), and having scalloped potatoes with ham for Easter dinner.

As I’ve said many times before, I am a huge fan of most any kind of potatoes. My mom’s cheesy & creamy scalloped potatoes have always been a favorite of mine. But we don’t make them very often. Recently, my sister downsized and was getting rid of some of her cookbook collection. While we have plenty of our own cookbooks, when she offered my an Irish cookbook, I could not refuse. I am so glad I didn’t!

While reading through said cookbook for St. Patrick’s Day recipes, I came across this recipe for sliced potatoes & mushrooms in a creamy, cheesy sauce. Even before trying it, I knew I wanted to feature it as an Easter side dish recipe. Once we tried it, I wanted to make it weekly and eat it every night. It’s that good! That probably won’t happen, but it will be the potato side dish we make often!

Potato & Mushroom Au Gratin

Potato & Mushroom Au Gratin (adapted from McGuire’s Irish Pub Cook Book by Jessie Tirsch) Total Time Required: about 1 hour, Prep Time: 30 minutes, Cook Time: 25 minutes, Makes: 6 -8 servings

Ingredients:

  • 2 pounds potatoes, peeled, sliced 1/8” thick
  • 1 tablespoon + 1-1/2 teaspoons salt, divided
  • 6 tablespoons unsalted butter, divided
  • 8 ounces fresh mushrooms, sliced
  • 1/4 cup all-purpose flour
  • 1-1/2 cups milk
  • 1/2 teaspoon white pepper
  • 2 tablespoons chopped fresh parsley, divided
  • 1-1/2 cups Cheddar cheese, divided
  • 1 cup fresh bread crumbs

Directions:

In a large saucepan, combine the potatoes with 1 tablespoon of the salt and enough water to cover the potatoes. Bring the pot to a boil over high heat, then reduce the heat to medium and cook the potatoes until they are firm-tender, about 10-12 minutes. Drain the potatoes and set them aside.

Cook the potatoes.

Drain the potatoes well.

While the potatoes are cooking, preheat the oven to 350ºF. Melt 2 tablespoons of the butter in a large skillet over medium-high heat. Add the mushrooms and cook, stirring once or twice, until the mushrooms are tender, about 3-5 minutes. Remove the mushrooms with a slotted spoon and set them aside.

Cook the mushrooms in some butter.

Melt the remaining 4 tablespoons of butter in a medium saucepan over medium-high heat. Whisk in the flour and cook, whisking constantly, until the flour turns a light golden brown color, about 3-4 minutes.

Make a roux with butter and flour.

Slowly stream in the milk, whisking constantly. Continue whisking and cook until the sauce is thickened, about 7 minutes. Stir in the white pepper and the remaining 1-1/2 teaspoons of salt. Remove the pot from the heat.

Add the milk & white pepper to the roux for the sauce.

Spray a deep 2-quart casserole dish with cooking spray and pour a quarter of the sauce into it. Arrange 1/3 of the potatoes over the sauce.

Add some sauce then some potatoes to the dish.

Spread 1/3 of the mushrooms over the potatoes and a teaspoon of the parsley.

Layer some mushrooms and a sprinkle of parsley over the potatoes.

Sprinkle 1/3 cup of cheese over the mushrooms. Repeat the sauce, potatoes, mushrooms, parsley, and cheese, layering twice more. Spread the remaining 1/4 of the sauce over the top of the last cheese layer.

Layer some cheese over the mushrooms and continue the layers, ending with the sauce.

Combine the break crumbs with the remaining 1/2 cup of cheese and 1 tablespoon of parsley.

Combine the bread crumbs with some cheese & parsley for the topping.

Sprinkle the crumb mixture evenly over the top layer of sauce.

It’s ready for the oven!

Bake the casserole, uncovered for about 25 minutes, until the bread crumbs are brown and the cheese is bubbly.

MMMM!!

Remove the dish from the oven and allow the casserole to rest for 5 minutes before serving.

Thanks for the awesome cookbook, Diane!  ~Linda

Potato & Mushroom Au Gratin (adapted from McGuire’s Irish Pub Cook Book by Jessie Tirsch) Total Time Required: about 1 hour, Prep Time: 30 minutes, Cook Time: 25 minutes, Makes: 6 -8 servings

Ingredients:

  • 2 pounds potatoes, peeled, sliced 1/8” thick
  • 1 tablespoon + 1-1/2 teaspoons salt, divided
  • 6 tablespoons unsalted butter, divided
  • 8 ounces fresh mushrooms, sliced
  • 1/4 cup all-purpose flour
  • 1-1/2 cups milk
  • 1/2 teaspoon white pepper
  • 2 tablespoons chopped fresh parsley, divided
  • 1-1/2 cups Cheddar cheese, divided
  • 1 cup fresh bread crumbs

Directions:

In a large saucepan, combine the potatoes with 1 tablespoon of the salt and enough water to cover the potatoes. Bring the pot to a boil over high heat, then reduce the heat to medium and cook the potatoes until they are firm-tender, about 10-12 minutes. Drain the potatoes and set them aside.

While the potatoes are cooking, preheat the oven to 350ºF. Melt 2 tablespoons of the butter in a large skillet over medium-high heat. Add the mushrooms and cook, stirring once or twice, until the mushrooms are tender, about 3-5 minutes. Remove the mushrooms with a slotted spoon and set them aside.

Melt the remaining 4 tablespoons of butter in a medium saucepan over medium-high heat. Whisk in the flour and cook, whisking constantly, until the flour turns a light golden brown color, about 3-4 minutes.

Slowly stream in the milk, whisking constantly. Continue whisking and cook until the sauce is thickened, about 7 minutes. Stir in the white pepper and the remaining 1-1/2 teaspoons of salt. Remove the pot from the heat.

Spray a deep 2-quart casserole dish with cooking spray and pour a quarter of the sauce into it. Arrange 1/3 of the potatoes over the sauce and spread 1/3 of the mushrooms over the potatoes. Sprinkle a teaspoon of the parsley and 1/3 cup of cheese over the mushrooms. Repeat the sauce, potatoes, mushrooms, parsley, and cheese, layering twice more. Spread the remaining 1/4 of the sauce over the top of the last cheese layer.

Combine the break crumbs with the remaining 1/2 cup of cheese and 1 tablespoon of parsley. Sprinkle the crumb mixture evenly over the top layer of sauce.

Bake the casserole, uncovered for about 25 minutes, until the bread crumbs are brown and the cheese is bubbly. Remove the dish from the oven and allow the casserole to rest for 5 minutes before serving.