Cannelloni al Radicchio

Ingredients

• 2 tablespoons extra-virgin olive oil
• 2 shallots,halved & thinly sliced
• 2 heads radicchio, quartered through the stem end, cored & finely shredded
• 1 tablespoon kosher saly, plus more as needed
• 1 pinch black pepper, plus more as needed
• 1½ cup whole cows milk ricotta, drained
• 8 ounces fresh mozzarella cheese, cut into small dice
• 1 ounce batch fresh egg pasta, cut into lasagna noodles
• 3 cups bechamel sauce, slightly heated
• 1 tablespoon unsalted butter
• 1½ cup parmigiano-reggiano, grated
• ¼ cup walnuts, coarsely chopped