Preheat your oven to 150°C. Drizzle your dish with olive oil.
Chop the leeks to 5cm chunks and stand them upright in the dish.
Cover with the remaining olive oil, salt & pepper, then roast for 45 mins or until soft, turning every 15 mins to make sure they don't burn.
To make the sauce, add all the ingredients to a pan. Stir on a low heat for 5-10 mins until well combined then set aside.
When the leeks are soft, remove from the oven. Place chunks of brie in between the leeks.
Cover with the sauce and cranberries. Bake for 30 mins until golden and crisp.
Top with the rest of the parmesan and enjoy.
