Preheat the oven to 200c/400f and line a baking tray with baking parchment or a silicone liner.
Unroll the pastry and brush with egg wash, then cut the pastry into approx 40 small rectangles. Place one rectangle on top of another and repeat with the rest of the pastry, so you have 20 or so ‘doubled up’ rectangles of pastry. Place on the prepared tray and bake for 10 minutes. Then take out of the oven.
Slice the Brie into small slices and place on top of the pastry puffs. Place back in the oven for 1-2 minutes to melt the brie.
Place the puffs on a plate and top each one with a small blob of cranberry sauce and a few fresh thyme leaves, then serve.