I use baking soda mixed in warm water. I don't like putting chemicals in there. I also make sure I wash off all the condiment bottles before I put them back in so I don't re-stickify everything. For the microwave, I put in half a lemon in about a cup of water, then run it for 5 minutes, then let sit for 5 minutes without opening the door. It will just wipe clean after that.