Chorizo Zucchini Boats

Ingredients (10)

• + 6 large zucchini, halved lengthwise add to pantry
• + olive oil cooking spray add to pantry
• + 1 tablespoon olive oil add to pantry
• + ½ red onion, finely chopped add to pantry
• ✓ 4 cloves garlic, minced
• + 1 pound fresh chorizo, casing removed add to pantry
• + 1 cup shredded mozzarella cheese, divided add to pantry
• + 2 large Roma tomatoes, chopped add to pantry
• + 1 tablespoon basil pesto add to pantry
• + 2 tablespoons grated Parmesan cheese, or to taste add to pantry