Cheesy Vegetable Lasagna

Makes 12 servings.

12 dry lasagna noodles
2 tablespoons olive oil
2 heads fresh broccoli, chopped
2 carrots, thinly sliced
1 large onion, chopped
2 green bell peppers, chopped
2 small zucchini, sliced
3 cloves garlic, minced
1/2 cup all-purpose flour
3 cups milk
3/4 cup Parmesan cheese, divided
1/2 teaspoon salt
1/2 teaspoon pepper
1 (10 ounce) package frozen spinach, thawed
1 (8 ounce) container small curd cottage cheese
24 ounces ricotta cheese
2 1/2 cups shredded mozzarella cheese, divided

Preheat oven to 375 degrees F (190 degrees C). Grease a 9 x 13 inch casserole dish. Bring a large pot of lightly salted water to a boil. Add lasagna noodles and cook for 8 to 10 minutes or until al dente; drain.

Heat oil in a large cast iron skillet over medium heat. When oil is hot add broccoli, carrots, onions, bell peppers, zucchini and garlic. Saut