An extraction assembly for use in an automatic brewer. The extraction assembly controllably extracts espresso beverage from a quantity of brewing substance. A brew chamber of the extraction assembly is removable for exchange with another brew chamber of different brew volume, having enhanced structures, or for replacement and repair. A heating element may be in close proximity to the brew chamber. Heat from the heating element can be brought directly to the area in which the coffee is brewed to help maintain a more consistent, tighter tolerance temperature and faster recovery between brew cycles.