apparatus for preparing hot beverages in a microwave oven has a lower carafe for receiving the finished brewed hot beverage and an upper reservoir having a bottom and retaining fresh water therein . the reservoir may be placed on the carafe and has a shut - off member disposed inside . the shut - off member has an inlet in the interior of the reservoir and an outlet extending through the bottom of the reservoir , and the shut - off member is a pipe which functions as a siphon or as an overflow . the reservoir is substantially air tight , and a vent is in the carafe for exhausting fluid from and into the carafe . alternatively , the reservoir is fluidly connected to the carafe and the carafe has a one - way valve for only exhausting fluid from the carafe .