Apparatus and methods for producing a foamed material. Pressurized gas is introduced into a multiple-component mixture that contains a catalyst-containing component and a crosslinker-containing component. The multiple-component mixture may be directly mixed and combined with the gas in a mixing device. Alternatively, the multiple-component mixture may be combined in a first mixing device and this mixture may be subsequently combined with the gas in a second mixing device. When dispensed onto an application target, the gas entrained in the multiple-component mixture expands to form the foamed material.