If you have small toaster ovens for home use and you dont remember when the last time you got it cleaned, then you should start by now. Toaster oven like any other appliances need utmost care and maintaining it from time to time will only add to its longevity. How you get it cleaned and when is your personal choice. You should get it cleaned as a routine of once a week. You can do any day if you see it to be messed. And when cleaning dont used hard scrubs as it may damage the coating. Instead use a soft cloth, sponge or plastic nylon pads which are mostly recommended. Use it with a mild soap solution to get it cleaned. There are many oven cleaning solutions available but they are mostly for exterior. IT wont suit the aluminum inside.
Dont immerse it with water. You will have to the solution to the sponge then clean up the inside of the oven. You small toaster ovens for home use have to be wiped up after every use. These will it to stay in good condition. So remember just wiping up after every use and deep cleaning once a week will make your toaster oven run for years. For interiors, the sponge should be damp and not drippy; you just have to wipe down any stains. Make sure that your oven is fully cleaned inside and out. You can use brush to remove stubborn stains. Once full cleaning is done, its time to give it some time to dry up. Once dries, you can use it again. Remember your ceiling and inside interior walls are the main areas which gets dirty upon regular use. So give special attention to it. Regular wiping up can make your weekly cleaning task easier. This is how you will have to get your toaster oven clean.