Cooking food in a dishwasher is an actual thing (!).
Lisa Casali, an Italian food writer has published cookbook called “Cucinare in lavastoviglie” / “Cooking in the dishwasher” and posted videos of the technique online. Apparently, there are lots of other people getting involved and posting their own videos and recipes. Seriously.
Technically, a dishwasher is similar to an oven in terms of the heat generated and there seem to be two main methods of dishwasher cooking.
Clean – use a clean, empty dishwasher, without any dishwasher tablets, so it is purely for cooking.
Environmentally friendly – wash your dishes as you would normally and stick in an airtight sealed container containing the food you want to cook at the same tight. The container would protect it from the dirt and soap.
The best food to cook in the dishwasher seems to be fish. Wrap it in some foil, stick it on a standard wash and voila! Fishwasher Supreme.