A method and apparatus for forming a beverage. An access opening for a reservoir of a brewer may be opened (e.g., to allow a user to provide liquid into the reservoir for forming a beverage), and thereafter, the access opening of the reservoir may be closed and the reservoir pneumatically sealed. The access opening may be closed and the reservoir pneumatically sealed by closing a lid of the reservoir, e.g., by a user pressing down on the lid. Pneumatic sealing of the reservoir may allow the water in the reservoir to be expelled from the reservoir for flow to the brew chamber by introducing air pressure into the reservoir, e.g., by an air pump. The reservoir may be vented during heating of the water, and during pressurization of the reservoir for delivery of the brew water.