An over-the-range appliance mountable over a cooktop appliance is provided. The over-the-range appliance includes a cabinet comprising a bottom panel defining a central aperture, a lighting box mounted within the central aperture. The lighting box defines a lighting recess and one or more light sources are mounted to the lighting box and are positioned within the lighting recess. A diffuser plate is positioned over the one or more light sources and encloses the lighting recess.