The Sea To Summit Kitchen Sink is packable solution to the problem of washing up while camping, partiularly on more basic campsites.
The Kitchen Sink is PVC free and has wide carry handles so can easily be used to collect water. The 10L capacity collapsing bowl can be used with hot water and detergent and the seams are fully taped. Its broad opening also makes it an excellent dog bowl. Included with its own storage pouch which handily has printed instructions on how to fold the bowl back down to fit it in.
No longer can you be accused of bringing everything but the kitchen sink, at only 134g you may as well bring it too.