Contributed by Laura Pensiero, Hudson Valley Mediterranean
1 tsp kosher salt
1 1⁄2 cups medium-grind stone-ground cornmeal (most brands found in the supermarket will work well)
1 tbsp olive oil
1⁄2 cup freshly grated Grana Padano or Parmesan cheese
1⁄4 cup olive oil, plus extra for the baking dish
2 lbs fresh shiitake and oyster mushrooms, tough stems removed, thinly sliced
5 or 6 fresh sage leaves, roughly chopped
2 tbsp chopped fresh flat-leaf parsley
1 1⁄2 tbsp all-purpose flour
2 cups half-and-half, or 1 cup 2% or whole milk and 1 cup heavy cream
Salt and freshly ground black pepper
1 1⁄2 cups shredded Fontina cheese
Bring 4 cups water to a boil in a medium heavy-bottomed saucepan. Add the kosher salt, reduce the heat to a simmer, and gradually whisk in the cornmeal, a small amount at a time. Reduce the heat to low and cook the polenta, stirring often, until tender, about 20 minutes.
Remove the pan from the heat and stir in the olive oil and Grana Padano. Pour the polenta into a shallow 9 x 17-inch baking dish and spread it out evenly with a spatula. Set aside until thoroughly cool.
Preheat the oven to 350F.
Heat the olive oil in a large nonstick skillet over medium-high heat. Add the mushrooms, sage, and parsley, and cook, tossing or stirring occasionally, until the mushrooms have released all of their liquid and are beginning to turn golden, about 12 minutes. Add the flour, stirring until it is no longer visible. Add the half-and-half and cook until the sauce is thick, 4 to 5 minutes. Season with salt and pepper to taste, and set aside.
Cut the cooled polenta into quarters. Then trim the quarters slightly so they will fit in a 13 x 9 x 2-inch (3-quart) baking dish. Grease the bottom and sides of the baking dish with olive oil, and place 2 slices of polenta on the bottom. Spoon half of the mushroom mixture over the polenta, and top it with half of the shredded Fontina.
Place the other two pieces of polenta over the cheese and top with the remaining mushrooms. Cover the baking dish with aluminum foil and bake until heated through, 20 to 25 minutes.
Increase the oven temperature to 400F. Remove the foil and top the “lasagna” with the remaining Fontina. Cook until the cheese is bubbly and golden, 10 to 12 minutes. Serve piping hot.