Preheat oven to 350°F. Lightly coat an 8-inch-square baking dish with cooking spray. Whisk 1 cup ricotta, ½ cup mozzarella, ½ cup cream, ½ cup Parmesan, beaten egg and ¼ teaspoon salt together in a large bowl until combined; set aside.
Heat 2 tablespoons oil in a large skillet over medium heat. Add cut asparagus, sliced zucchini, chopped onion and minced garlic; cook, stirring occasionally, until the vegetables are softened and slightly browned, about 7 minutes.
Add thawed peas, 2 tablespoons basil, ½ teaspoon crushed red pepper and the remaining ½ teaspoon salt. Cook and stir until fragrant, about 1 minute. Add chopped spinach in handfuls, stirring until just wilted before adding more, about 5 minutes.
Add the zucchini mixture and cooked penne to the large bowl with the ricotta mixture; fold until evenly coated. Transfer the mixture to the prepared baking dish; sprinkle evenly with the remaining ½ cup mozzarella.
Bake until the cheese is melted and the pasta mixture is heated through, about 15 minutes. Garnish with basil, if desired.
