Abstract: A mixer for combining solid material such as asphalt shingles and/or recycled asphalt with asphalt binder. A method of using the mixer includes inputting large chunks of solid material to a first inlet of the mixer, inputting liquid asphalt binder to a second inlet of the mixer, passing the large chunks of solid material and the asphalt binder through a mixer chamber having a first stage and a second stage, the first stage comprising a helical screw and the second stage comprising a plurality of paddles, and obtaining a uniform mixture comprising small chunks of solid material and asphalt binder from the mixer.