Step 1Heat 2 tablespoons oil in large, heavy saucepan over medium heat. Add sausage and cook until browned on all sides and thoroughly cooked, 15 to 20 minutes. Remove and set aside. Add onions and garlic. Cook onions until translucent, 5 minutes. Add wine and cook over medium-high heat until reduced to a glaze, stirring occasionally, 3 minutes.
Step 2Add tomatoes, tomato juice, basil, oregano, thyme, bay leaves, salt and pepper to taste and dash sugar. Bring to a boil. Reduce heat and simmer 30 minutes, stirring occasionally. Remove from heat and stir lightly to blend well. Slice sausage and add to sauce.
Step 3Combine radicchio with remaining olive oil and salt and pepper to taste in a heat-proof dish. Bake at 350 degrees 5 minutes or until radicchio is wilted. Set aside to cool.
Step 4Spread a thin layer of sauce in bottom of a 13x9-inch baking dish. Arrange 1 layer of pasta sheets over sauce. Spread another layer of sauce over sheets. Sprinkle with 1/2 cup ricotta salata and 1/4 cup Fontina. Arrange a second layer of pasta sheets and a second layer of sauce over Fontina layer. Cover sauce with thin layer of radicchio leaves and sprinkle with more ricotta salata. Top with a third layer of pasta and cover with more sauce, ricotta salata and Fontina. Arrange a fourth layer of pasta and cover with sauce. Top sauce with remaining Fontina.
Step 5Cover lasagna with foil and bake at 350 degrees until thoroughly hot, 30 to 45 minutes. Remove foil and bake at 450 degrees until surface is golden brown. Cut into squares and serve.