Preheat oven to 350°F. Lightly grease a 5-inch cast-iron skillet, or line a small baking sheet with parchment paper and set aside.
Slice the top rind off the wheel of Brie, leaving rind on the bottom and sides. Place the Brie bottom side down in the skillet or on the pan and sprinkle with 1 tablespoon of light brown sugar.
Bake for 12-15 minutes until cheese is bubbly and soft.
Compote:
Meanwhile, begin making the compote by whisking together the apple juice or cider, corn syrup, and 1 tablespoon light brown sugar in a small saucepan. Boil over high heat until reduced in half, about 5 to 7 minutes.
Add in 2 tablespoons of butter and stir until melted, then remove from heat.
Melt the other 2 tablespoons of butter in a large skillet over medium heat. Add the apple pieces and cook for 2 minutes, coat them with the butter and stirring occasionally.
Add in the cranberries and sugar and stir frequently until cranberries begin to pop, about 2 minutes.
Stir in the apple juice mixture and boil until reduced to a syrup consistency. Use the back of the spatula to squish the cranberries.
Spoon compote over the baked Brie and sprinkle with nuts and drizzle with maple syrup just before serving. Serve with toasted baguette slices or crackers.
Notes
Compote can be made one day ahead of time, store in the fridge in an air-tight container. Warm up in the microwave before topping the Brie with it.