Preparation Preheat oven to 400°F. Oil 11x7x2-inch glass baking dish. Remove stems from mushrooms and chop finely; place in prepared baking dish. Using small spoon, scrape away dark gills from underside of mushrooms and discard. Cut each mushroom cap into 8 wedges; add to baking dish with chopped mushroom stems. Drizzle with 1 1/2 tablespoons oil. Sprinkle with 1 minced garlic clove, parsley, salt and pepper and toss to coat. Bake until tender, 25 minutes. Meanwhile, combine 4 cups water and 1 1/2 teaspoons salt in large saucepan. Bring to boil. Gradually whisk in polenta. Reduce heat to low. Cook until polenta thickens and begins to pull away from sides of pan, whisking often, about 25 minutes for polenta or 15 minutes for yellow cornmeal. Whisk in butter, then cheese. Season with salt and pepper. Heat 2 tablespoons oil in large pot over medium-high heat. Add 2 minced garlic cloves and sauté 30 seconds. Add Swiss chard and spinach and sauté until tender but still bright green, about 4 minutes. Season with salt and pepper. Spoon polenta onto plates. Top with greens and portobello mushrooms.
Preparation Preheat oven to 400°F. Oil 11x7x2-inch glass baking dish. Remove stems from mushrooms and chop finely; place in prepared baking dish. Using small spoon, scrape away dark gills from underside of mushrooms and discard. Cut each mushroom cap into 8 wedges; add to baking dish with chopped mushroom stems. Drizzle with 1 1/2 tablespoons oil. Sprinkle with 1 minced garlic clove, parsley, salt and pepper and toss to coat. Bake until tender, 25 minutes. Meanwhile, combine 4 cups water and 1 1/2 teaspoons salt in large saucepan. Bring to boil. Gradually whisk in polenta. Reduce heat to low. Cook until polenta thickens and begins to pull away from sides of pan, whisking often, about 25 minutes for polenta or 15 minutes for yellow cornmeal. Whisk in butter, then cheese. Season with salt and pepper. Heat 2 tablespoons oil in large pot over medium-high heat. Add 2 minced garlic cloves and sauté 30 seconds. Add Swiss chard and spinach and sauté until tender but still bright green, about 4 minutes. Season with salt and pepper. Spoon polenta onto plates. Top with greens and portobello mushrooms.