1. Position a rack in center of oven and heat oven to 375 degrees .
2. Place sugar in a small bowl. With a sharp knife, split vanilla bean in half lengthwise and scrape seeds into sugar (reserve the vanilla pod). Work sugar, vanilla seeds and lemon zest together with your fingertips until sugar is fragrant and moist-looking.
3. Arrange fruit in a 9 x 13-inch metal baking dish, cut side up. Drizzle with lemon juice and sprinkle with sugar. Dot butter bits all over fruit. Add vanilla pod and 2 tbsp water to dish.
4. Roast at 375 degrees for 30 minutes, occasionally spooning pan juices over fruit. Turn fruit and continue to roast, basting once or twice, until tender, 15 to 20 minutes more.
5. Serve with ice cream, yogurt or creme fraiche, if using.
6. Excerpt from Real Sweet by Shauna Sever