- With the rack in the middle position, preheat the oven to 425°F (220°C).
- In a large baking dish, toss the sausages with half of the oil. Bake for 15 minutes or until golden. Flip the sausages over and add the grapes lemon juice and remaining oil. Bake for another 10 minutes or until the sausages are cooked and the grapes have burst. Remove from the oven. Add the green onion and rosemary.
- Drizzle with the pan juices and serve with mashed potatoes, if desired.