Here is a cool, green way to clean up your grubby microwave. Put a small microwave safe container in the centre of the microwave. Fill it up with white vinegar. Heat the vinegar and let it boil for a minute or so!
Then use rubber gloves and wipe down with a soft cloth dipped into the hot vinegar!
To keep your microwave clean always keep a lid of some sort on the container (not metal) when cooking. This will be the guard that prevents messy food splatters on the inside! You can also cover the carousel tray with wax wrap. Put a fresh piece on when you need to, and your oven will remain fresh all the time!
From: Haley’s Cleaning Hints.