Combine dry polenta, Parmesan and seasonings. Cut cold polenta into bite-sized pieces. Press polenta into dry mixture, patting on as much as possible. Heat oil in a skillet until shimmering. Add polenta pieces in a single layer without crowding pan and cook until crispy, turning a few times, approx. 5 min total. Drain and set aside; keep warm until ready to assemble salad.
Spring Greens and Warm Pancetta Salad
Heat oil in skillet with diced pancetta. Cook pancetta until crisp, 3 min. Remove pancetta from pan. Add shallots to hot oil, cooking 3 min until golden brown. Add vinegar, seasonings and tomatoes, tossing well to combine. Place lettuce on four serving plates, spooning warm tomato mixture over each salad. Sprinkle pancetta over each and finish with warm polenta croutons. Serve immediately.