The microwave oven for preparing popcorn composition, comprises a chamber having a puffed popcorn composition, a stockage chamber with a non-puffed composition and a susceptor allows the puffing of the composition when an axis of the oven exhibit >=20[deg] and =10[deg] with respect to a vertical axis. The stockage chamber (4) is disposed in the chamber. The stockage chamber is partially covered by the susceptor and opened towards a lower side (11) of the oven. Partition is bounded by a fixation part. The popcorn composition comprises a corn, oil and/or fat material. An independent claim is included for a process of popcorn preparation.
