I just fished some romex up the wall, from the switch up to on top of the cabinets, where i knocked a small hole in the drywall. Wired up an old electrical work box to the transformer, from there to the dimmer. lights wired to dimmer ,then just left it all laying on top, where it is not seen from floor level, but the rheostat is still reachable. Easy peasy. Everyone who comes over is always amazed at the under cabinet lights without the cords hanging down to a plug.