Spring Vegetable Lasagna

Ingredients

• Cooking spray
• 8 cups torn Swiss chard (about 3/4 pound)
• 2 cups chopped yellow squash
• 1 1/2 cups chopped onion
• 1 cup chopped red bell pepper
• 1 cup shredded carrot
• 1/2 teaspoon salt
• 1 tablespoon butter
• 4 garlic cloves, crushed
• 2 tablespoons all-purpose flour
• 1 1/2 cups fat-free milk
• 6 tablespoons (1 1/2 ounces) grated fresh Parmesan cheese, divided
• 1 cup fat-free ricotta cheese
• 1 cup fat-free cottage cheese
• 1 cup (4 ounces) grated Asiago cheese, divided
• 1/2 teaspoon dried oregano
• 6 no-boil lasagna noodles (such as Barilla or Vigo)