1. Preheat oven to 425°. Cook pasta according to package directions in salted water; reserve 1/4 cup pasta water. Add peas during last 2 minutes of cooking; drain pasta and peas and return to pot.
2. While pasta cooks, toss carrots on a large rimmed baking sheet with 1 tablespoon oil and 1/4 teaspoon each salt and freshly ground black pepper. Roast carrots 15-18 minutes; toss pasta, reserved pasta water, and peas with carrots, mint, and remaining 1 tablespoon oil in pot. Divide among 6 bowls.