Spaghetti with Grilled Zucchini Sauce — Three Many Cooks

Ingredients

• 12 ounces thin spaghetti
• 8 Italian plum tomatoes, halved
• 2 medium-large zucchini, cut into rounds on a slight diagonal
• 1 large red onion, cut into thick slabs
• 1 small whole garlic head
• ¼ cup olive oil, divided
• 2 teaspoons dried oregano
• Salt and ground black pepper
• ¼ cup pitted kalamata olives
• ½ cup crumbled feta cheese, divided