3/4 pounds cremini mushrooms, cleaned and cut in half or 1-inch pieces
4 sprigs thyme, plus extra for garnish
6 cloves garlic, paper removed
1/4 cup extra virgin olive oil
2 tablespoons unsalted butter
1 cup polenta
4 ounces grated parmesan, plus extra for garnish
1 tablespoon red wine vinegar
Kosher salt and fresh ground black pepper
Heat the oven to 325 F. Prepare a large baking sheet by covering it in aluminum foil, and set aside.
In a large mixing bowl, combine the cremini and shiitake mushrooms, thyme sprigs, garlic, olive oil, salt and pepper. Toss to fully coat the vegetables.
Arrange vegetables in a single layer on the prepared baking sheet.
Place the vegetables in the oven and allow to roast while preparing the polenta.
Bring 4 1/2 cups of water (or chicken stock) to a rolling boil.
Season the water by adding butter and salt, and whisk to combine.
Slowly add the polenta to the water, whisking constantly to avoid lumps.
Bring back up to a simmer and continue to cook, stirring frequently, until the polenta becomes thick and creamy, about 25 to 30 minutes.
Turn up the oven to 450 F to crisp the vegetables for another 10 to 15 minutes while you finish the polenta.
Slowly add the parmesan cheese to the polenta and stir it in until well mixed.
Taste and adjust seasonings with salt and pepper.
Cover the polenta and allow it to sit until mushrooms are finished roasting.
Remove the mushrooms from the oven and discard the thyme sprigs.
Drizzle the mushrooms with red wine vinegar. Carefully toss the mushrooms and allow to cool slightly.
Transfer the polenta into a large serving dish, and top polenta with roasted mushrooms and garlic.
Garnish with an extra drizzle of olive oil, fresh thyme leaves and/or extra grated parmesan.