You would actually want to powder coat, which is a whole system in itself. see.
Plating Kits Electroplating Kits Aluminum Anodizing Kits Powder Coating Systems Metal Polishing And Buffing Supplies - Caswell Inc. It does have a baking step.
Hinges can be plated. I can't find my bookmark for an online company that will do it. If really interested, I can try to locate the company again.
Bathrooms would benefit by a powder coat system better than anything else.
It isn't recommended to use a baking over, but rather a separate oven like a toaster oven for potentially toxic processes. Baking enamel is just going to make a mess.
The next best thing would be a two part epoxy paint sprayed on. This could be found at a marine store. There are small very low-cost paint systems at the hardware store that use a propellent cartridge and a container. Two-part epoxy paint also doesn't come cheap.