Cut your camembert in half. Place a bottom half in the middle of your pastry circle. Top this half with onions and bacon. Top with the other half (cut-side down). Make 8 incisions in your pastry at 12, 3, 6 and 9 o'clock respectively, followed by 4 more in between each of these initial cuts.
Using a small round object as a guide, cut a circular line at the end of each 'flap' continue all around the pastry until you have a flower shape.
Fold one flap up and brush with egg wash. Repeat with all of the flaps. Sprinkle over a little flaked salt and bake for 20 minutes at 210°C.