Remove the cabinet doors from the cabinet housing by unscrewing the hinges with a screwdriver. Remove the handles or any other hardware by unscrewing them as well.
Wipe down the cabinet doors and housing with soapy water and a damp sponge. Let the cabinets air-dry.
Open a can of black glaze and mix it with a paint stirrer. Pour the glaze into a small bowl.
Dip a rag or foam paintbrush into the glaze and apply it to the cabinets. Use even strokes for a more uniform application or a circular motion for a weathered look. Apply the glaze in 6-by-6 inch sections.
Wipe the glaze off the cabinet with a clean cloth as you complete each section. If the effect is not dark enough, apply another layer and wipe it off. Continue until you have applied glaze to all sections of the cabinets and removed the excess with a rag.
Let the glaze dry according to the package directions. Replace the hardware and hinges, and hang the cabinets back in their housing.