Cut Brie cheese horizontally in half, creating two equal rounds similar to a layered cake. Spread pesto sauce on the cut surface of 1 half; sprinkle pine nuts and brown sugar over pesto layer. Place the other Brie half on top of pesto mixture.
Separate crescent rolls and cover entire Brie round with crescent roll dough, sealing all the gaps. Place covered Brie on a baking sheet.
Bake in the preheated oven until Brie cheese is softened and crescent rolls are lightly browned, about 20 minutes.