Mascarpone Polenta with Wild Mushrooms

Name: Mascarpone Polenta with Wild Mushrooms
Ingredients: 1½ cups polenta or ground corn; 1 tablespoon unsalted butter; ½ cup fresh or frozen sweet corn kernels; 2 tablespoons mascarpone; Kosher salt; White pepper; 2 tablespoons extra-virgin olive oil; 5 cups thinly sliced mixed mushrooms (such as chanterelles, cremini, shiitake, beech and oyster); 1 small shallot, finely chopped; 2 garlic cloves, finely sliced; ½ tablespoon finely chopped chives; ½ tablespoon finely chopped flat-leaf parsley; White truffle oil; 2 tablespoons finely grated parmesan