How to Clean a Microwave
Ah, the microwave. To some it is merely an accessory to all of the wonderful cooking appliances their bags of money to buy, and to others it is the only thing they know how to cook with--be it ramen, macaroni and cheese, or exhorbatantly priced chicken pot pie. Who invented this miracle of modern cuisine? No one knows. It's origins are as shrouded in mystery as the whereabouts of the Ark of the Covenent, which was later found by the Germans who were then exploded by microwaves when they opened it. What we do know is that tthe microwave oven is the pinnacle of human engineering, and the cause of many exploded bowls of soup. If exploded bowls of soup, or better yet a starchy stew, are your problem, we have the solution. Below, I will teach you the fine art of how to clean a microwave, and cleaning a microwave the way god intended. If only those Germans had listened to Indiana Jones and we had listened to our mother's incessant nagging about putting wax paper over our bowls of beef stew.
Cleaning a Microwave
If your microwave has a removable tray, you'll want to take that out before you start cleaning. If the microwave tray is really stained or has a lot of crap stuck to it, you may want to soak it in a sink with natural dishwashing liquid. I say use a natural dishwashing liquid because eventually you'll use this tray to heat food, and you don't want nasty cleaning agents getting into your food, now do you?
Use a paper towel to scrape away any crusties or crumbs that you can. This will make cleaning a microwave that much easier because you won't be smearing anything that might be water soluable all over the rest of your microwave. Just scrape away what you can with the paper towel and throw that junk in the garbage.
Use a natural solvent like vinegar to soak the stains briefly. Allow the vinegar to do its magic. Vinegar is an acid and a powerful natural cleaning solution that is in no way toxic if it ends up in your food. Once you think you've loosened up the stains, or have scrubbed them out with a scotch pad, wipe them out with a dry paper towel. If you use vinegar, you don't have to worry about any leftovers because it'll safely evaporate on its own.
Wash the microwave tray off with a natural dishwashing liquid like Ecover. I've said it once, and I'll say it again; I don't trust other cleaning agents like all-purpose cleaners, or unnatural dishwashing liquids near my food. I won't get on a soapbox (pun intended) and preach to you about the environment and the damage that cleaning detergents do to it--just be aware that there are alternatives to Dawn and Clorox.
Dry the microwave tray and put it back in the microwave, allowing the clean microwave to air out for a while. Make sure you get those little teeth in the tray aligned with the revolving mechanism, or your next bowl of soup may end up all over your microwave, again. Let the microwave sit for at least an hour to allow any moisture left over to evaporate before you plug that sucker in and cook yourself some canned chili.
Microwave Cleaning Products
I'll be honest with you; I had no idea such a thing existed until I did a google search for "microwave cleaner." Apparently there is such a thing, and they're made by Easy-Off. The procedure is quite simple, according to some nameless person's review of the product. Simply put the pouch in the microwave and allow it to heat for 60 seconds. The pouch will pop open during this time. Allow the pouch to sit for three minutes and then wipe your problems away. If only life was that easy. But I'll tell you something, I don't trust it. Something tells me that if heat is necessary to cause some sort of chemical reaction in this product, then I doubt it's safe. As a rule, I say this: if you can eat it and not end up in the emergency room afterwards, then it's safe to clean your cooking appliances with. Personally, I'd go with something from Seventh Generation or Ecover before Easy-Off's solution. That's just me.
Natural Microwave Cleaning Options

Seventh Generation all purpose cleaner is something special. How can you go wrong with a list of "features" like this:
Non-toxic
No fumes
Biodegradable
No harsh chemicals
No petroleum based solvents
No glycol ethers
No phosphates
No acids
No caustics
No dyes
No fragrances
and most importantly Not tested on animals.

Plain White Vinegar is the cleaning solvent of choice. It's got acids, acids that kill things and wipe away the toughest, nastiest, grossest things you can throw at it. It smells bad at first, but that's just its way of showing you how much it's going to kick your microwave mess in the bum.

Boiling water in your microwave is a great way to loosen up tough chunks of whatever has exploded in your microwave. It's a great, chemical-free way to clean your microwave, while saving yourself a little elbow grease for other cleaning projects.

