1. Preheat oven to 400°. Coat a baking sheet with cooking spray.
2. Cook pasta according to package directions; drain.
3. Toss grapes with 1 teaspoon olive oil and 1/4 teaspoon salt. Place on baking sheet. Roast 5–7 minutes, or until first few grapes begin to split. Remove from oven and let stand.
4. Heat remaining olive oil in a nonstick skillet over medium-high heat. Add onion and thyme; cook until onion is softened, about 4 minutes. Pour in broth and wine; boil 5–6 minutes, or until sauce is amber-colored and no longer tastes of "raw" wine.
5. Combine pasta and sauce; toss with grapes and feta.