Wild Mushroom and Parsnip Ragout With Cheesy Polenta recipes

Name: Wild Mushroom and Parsnip Ragout With Cheesy Polenta recipes
Ingredients: 2 tablespoons olive oil, divided; 1 small onion, coarsely chopped (about 3/4 cup); 1 garlic clove, finely chopped; 1 thyme sprig; 1 medium parsnip (about 7 ounces), peeled, finely chopped; 12 ounces mixed wild mushrooms, such as maitake, shiitake, porcini, and/or crimini, cut into 1/2 pieces; 1 tablespoon miso paste; 1 tablespoon tomato paste; 1/2 teaspoon cornstarch; 1 3/4 teaspoons kosher salt, divided, plus more; 1/4 cup red wine; 1 cup quick-cooking polenta; 5 cups (or more) whole milk; 1/2 cup grated Parmesan, divided; 1/4 cup roasted, unsalted hazelnuts, chopped