01 -
Preheat oven to 375°F (190°C). Lightly dust a work surface with flour and roll out the puff pastry sheet to approximately 13 x 11 inches. Place the pastry onto a parchment-lined baking sheet.
02 -
Using a sharp knife, score a border 1 1/2 inches from the edge all around the pastry. Prick the central area with a fork to prevent excessive puffing.
03 -
Evenly spread the jam inside the scored border. Layer the sliced Brie over the jam, sprinkle with thyme leaves, and season with freshly ground black pepper.
04 -
Fold the edges of the pastry over the filling, pleating as necessary for a rustic appearance. Brush the exposed pastry border generously with beaten egg.
05 -
Bake for 30 to 40 minutes until the crust is puffed, deeply golden, and crisp.
06 -
Allow the galette to cool slightly. Slice and serve warm or at room temperature.