To freeze: Line 13x9-inch (3-quart) glass baking dish with plastic wrap, leaving enough overhang to completely enclose assembled lasagna. Cool filling and sauce completely, covered, 30 to 40 minutes in refrigerator before assembling lasagna. Assemble lasagna in dish; cover with another layer of plastic wrap. Freeze unbaked lasagna about 8 hours or until completely frozen. Transfer frozen lasagna to labeled 2-gallon resealable freezer plastic bag. Place remaining 1/3 cup hazelnuts in 1-quart resealable freezer plastic bag, and store in same freezer bag with lasagna. Remove air; seal and freeze up to three months. To bake: Remove plastic wrap, and transfer to 13x9-inch (3-quart) glass baking dish sprayed with cooking spray. Cover tightly with foil; thaw in refrigerator until completely thawed, up to 48 hours. Heat oven to 400°F. Bake 55 minutes; remove foil. Top with remaining 1/3 cup toasted hazelnuts. Bake 15 to 18 minutes or until bubbly and lightly browned (165°F in center). Let stand 15 minutes before cutting.