directions
1. Preheat oven to 450°F. Line 2 rimmed baking sheets with foil and spray lightly with cooking spray. Arrange polenta slices on trays and spray top sides lightly with more cooking spray (or brush both sides with olive oil if you prefer). Roast until polenta is lightly golden brown at edges, about 25 mins.
2. Heat 1 tablespoon olive oil in a heavy saucepan over medium heat, add shallots and sauté until softened, about 5 mins. Add baby kale and stir until wilted, about 3 mins. Remove from pan and set aside. Wipe pan clean with paper towel.
3. Heat remaining olive oil over medium-high heat. Add mushrooms and cook, stirring frequently, until tender and starting to crisp at edges. Add salt and pepper to taste.
4. Top roasted polenta slices with kale mixture, mushrooms, white beans, and cheese (if using). Return to oven until cheese melts, about 2 minutes, then arrange on a platter and serve