Most of the matter in the universe is widely thought to be non-baryonic and composed of unknown subatomic particles referred to as dark matter. While significant attention has been paid to a few specific candidates such as the WIMP and axion, in fact the nature and mass of dark matter is poorly constrained, and thus a broad observational approach may yield useful clues for its ultimate detection. We have developed a novel approach which utilizes the recent Breakthrough Listen public data release of three years of observation with the Green Bank Telescope to execute a broad search for an axion signal across billions of independent frequency channels simultaneously. This method is model-independent and only assumes that there is a decay or annihilation of virialized dark matter leading to a quasi-monochromatic radio line, and additionally that the line exhibits a Doppler shift with position according to the solar motion through a static galactic halo. This approach has been tested on a subset of L-band data, and the analysis of the full L-, S-, C- and X-band dataset (25,000 spectra, 1.1–11.6 GHz) is currently underway. This work was supported by a grant from the Heising-Simons Foundation.