How do you clean brass kitchen cabinet hardware?

Remove them and coat them in regular old ketchup for about 15 minutes . The acid will clean them right up. Rinse, dry and re-install .

Soap and water work wonders!

Remove the hardware and soak it in a brass cleaning solution (you can make one at home out of vinegar and baking soda). After a good soaking, brush it with a soft brush and wipe with a cloth

I've cleaned brass items for years while using the same product! Brasso metal polish for brass, pewter, chrome, copper & stainless. It's quite amazing! I use it on my copper and brass jewelry too. It's a product that has been around for many years and you can find it at many places like Wal-Mart, Kroger, etc.. I always have a bottle on hand. The first container that came out was metal and is still sold today while many are now plastic bottles. Just put some on a cloth and rub onto the item, let sit & dry then polish with a dry cloth. Done! I have never used any other type of brass or copper cleaner because there is no need too!!!! Good luck!