Cheesy Polenta Mushroom Gratin (low FODMAP)

30 Minutes prep • 45 Minutes cook • Low FODMAP • Gluten-free • Vegetarian • Serves 8 • Ok to make-ahead: Steps 1 - 3 or 1 - 7

A favorite vegetarian dish that can be served as a main course, or side, and can be fully prepared ahead of time and finished in the oven. This polenta mushroom gratin is hearty, creamy, flavorful, and satisfying. The cheese, herbs, and cream blend perfectly with the creamy polenta and the mushrooms add a depth of flavor that is truly special.

Ingredients: Polenta

4 cups boiling water

1 1/2 cups coarse cornmeal (polenta)

1 tablespoon butter

1/2 cup fresh grated parmesan cheese

1/2 cup grated extra-sharp cheddar

Kosher salt* and black pepper*

Ingredients: Mushrooms

2 tablespoons garlic-infused olive oil

2 tablespoons butter

1 pound oyster mushrooms, chopped

1 teaspoon Gourmend garlic scape powder* (use code IBSGC15 for 15% discount)

1 teaspoon Smoke N Sanity Essence of Garlic Salt* (use code IBSGC10 for 10% discount)

3 teaspoons fresh thyme leaves, chopped (or 1 teaspoon dry thyme*)

1/2 teaspoon fresh ground black pepper

Kosher salt

Ingredients: Cream sauce

2 tablespoons butter

2 tablespoons gluten-free flour (I used Bob’s Red Mill*)

2 cups lactose-free whole milk, half and half, or cream

Mushroom juices (if any from the pan you cooked them in)

1 teaspoon Kosher salt

1/2 teaspoon black pepper

Ingredients: Gratin

3/4 cup Parmesan cheese, freshly grated

1 1/2 cups fontina cheese, grated

Directions

(1) Prepare: Grease an 8” x 8” pan with butter. Grate the cheeses. Boil the water for the polenta.

(2) Cook polenta: Put the boiling water, butter, and polenta in a microwave-safe bowl with sides high enough to prevent boil-over.

Heat in microwave on high for about 6 minutes (if you start with cold water you will need to double this time). Remove from microwave and stir well to remove any lumps. Return to microwave and cook for 2 - 4 more minutes until nicely thickened. Stir in cheese, salt, and pepper.

(3) Cool polenta: Spoon polenta into prepared pan. Push the polenta into the edges of the pan and smooth the top. Set aside to cool.

Make-ahead note 1: At this point, you can cool the polenta, then refrigerate until ready to assemble the gratin. Polenta will keep, tightly covered, in the refrigerator for several days.

(4) Preheat oven to 350 degrees F.

(5) Cook the mushrooms: Heat the butter and olive oil in a large skillet until the butter melts. Add the mushrooms and stir until all mushrooms are coated. Reduce the heat and add garlic scape powder, essence of garlic salt, black pepper, and fresh or dried thyme leaves. Stir well and continue to cook until the mushrooms are softened and have released their juice. Taste and add additional Kosher salt if needed. Set the mushrooms aside.

(6) Make the cream sauce: In a medium saucepan, melt the butter over medium heat. Add the flour and stir constantly and cook for 2 - 3 minutes. Slowly whisk in the milk, half and half, or light cream then add any juices from the mushroom pan. Keep whisking until the sauce is thickened and smooth. Add the salt and pepper. Stir well then taste and add more salt and/or pepper if needed.

(7) Assemble the gratin: Turn the polenta out from the pan to a cutting board. Slice evenly in 1/2 - 3/4 inch pieces and set aside.

In the 8” x 8” pan you used to cook the polenta, or in another baking dish if you prefer, put a bit of the cream sauce in the bottom of the pan. Arrange one layer of polenta slices on top of the sauce. Next, layer on half the cooked mushrooms, and half the Parmesan and fontina cheese, over the polenta. Sprinkle with a good grinding of black pepper and half the remaining cream sauce. Arrange one more layer of polenta slices, mushrooms, cheese, and sauce, finishing with the sauce. (If you have some polenta left-over, wrap tightly in plastic wrap and refrigerate then use it to make our savory polenta cakes.)

Make-ahead note 2: At this point, you may cover with parchment and then with foil (so the foil doesn’t stick to the cream sauce layer) and refrigerate until ready to bake.

(8) Bake the gratin: Cover with parchment and then with foil (so the foil doesn’t stick to the cream sauce layer) and bake for 30 minutes, or until the sauce is bubbling (it will take 10 - 15 minutes longer if you refrigerated the gratin before putting it in the oven). Remove the foil and parchment covering and bake for another 5 - 10 minutes.

(9) Plate and serve: Let cool for a few minutes or until it stops bubbling before serving. Serve with a sprinkling of fresh thyme leaves and additional Parmesan cheese on the side. If you have leftovers, cool and store, tightly covered, in the refrigerator. Cut pieces heat up perfectly in the microwave so this makes a great lunch or follow-on dinner.

Eat and enjoy every bite because you can!

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