A popcorn popping unit comprises a blower unit and a popping vessel. The popping vessel has first and second parts assemblable with one another to form the popping vessel. The first part is operatively mounted on the blower unit and the second part has an opening configured to vent pressurized air generated by the blower during cooking operations from the popping vessel through the opening. The popping vessel has at least a portion with inner and outer walls spaced apart from one another to form a double wall construction for the at least portion of the popping vessel. The inner wall may comprise glass and the outer wall may comprise plastic. The inner and outer walls may be transparent.