Coat a shallow metal roasting pan with cooking spray. Add mushrooms, zucchini and yellow squash, bell pepper and onion.
2In a small dish, combine vinegar, oil, garlic and rosemary; brush evenly over vegetables. Bake vegetables for 15 minutes and toss. Continue baking 8 to 10 minutes longer or until vegetables are browned and tender.
Spoon 1 cup spaghetti sauce over the bottom of a 13 x 9- inch baking dish. Arrange 4 pieces of lasagne (3 lengthwise, 1 width-wise) over the sauce. Cover lasagne with 1 cup sauce.
3In a medium bowl, combine ricotta cheese, spinach, egg white and hot red pepper flakes. Drop half the cheese mixture by spoonfuls over sauce; arrange half of the roasted vegetables between spoonfuls of cheese mixture.
Arrange another 4 pieces of lasagne over cheese and vegetables, pressing lightly; top with 1 cup sauce.
4Repeat layering with remaining cheese, roasted vegetables, 4 pieces of lasagne and remaining sauce.
Reduce oven temperature to 375 degrees F.
5Cover lasagne with foil; bake 45 minutes. Uncover; sprinkle with mozzarella and Parmesan cheese; continue baking, uncovered, 5 minutes or until cheese is melted. Let stand 10 minutes before serving.