Cut the pumpkin into 4 mm slices
Cut discs out of the pumpkin.
Place the pumpkin discs and the olive oil, ginger and vanilla in a vacuum bag and remove the air
Steam the pumpkin discs for 30 minutes at 100°C.
The pumpkin should be very slightly overcooked, so that it has a custard-like texture but does not lose its shape.
Cool the pumpkin in ice water straight away and refrigerate in the vacuum bag.
Immediately before serving, heat the pumpkin in the vacuum bag or under a heat lamp.