Pour some water into your glass of ouzo, and the beverage will change from
transparent to milky. We demonstrate that the oil nanodroplets self-organize in universal branching patterns when the ʻOuzo effectʼ is confined to a quasi-2D geometry. The formation of these nanodroplet branching patterns is governed by the interplay between the local concentration gradient, diffusion, and collective interactions. Pictured is a visualization of the autonomous motion of colloidal particles driven by local concentration gradients around the droplet branch structure.