Place the cheese round on a lined baking sheet or you can use a small, oven-safe dish such as Corningware. Add the preserves to the top of the cheese, spreading evenly. Then top with the nuts, if using.
Bake for 10-12 minutes, or until the brie is warm and soft. You want it to be soft enough for serving but not a melted mess. It needs to still hold its shape when serving.