Amidoamine-based gemini surfactants having dual chains connected via an alkyl linker. Each chain contains a quaternary ammonium head group and an ethoxylated alkyl tail. Properties of the surfactant including thermal stability, critical micelle concentration, and foam stability are specified. A method of recovering oil from a reservoir using an aqueous composition that contains the surfactant and a polymer (e.g. AM-AMPS) is also provided. This method is particularly effective for oil recovery in reservoirs of high temperature and/or high salinity.