To clean a microwave with burnt-on food on the inside, proceed as follows: remove the turntable and rinse it in gentle soapy water. Wipe the interior with a damp cloth. Allow the soapy water to soak into the burnt-on remains. Don’t turn the microwave on while the water is soaking. Then, wipe the interior with a soft cloth. Don’t use the rough side of a universal sponge for cleaning your microwave or to remove burnt-on remains. This can scratch the interior. Oven cleaner should not be used under any circumstances. It’s far too aggressive. It’s better to clean the microwave immediately after warming and preparing food rather than leaving it too long. In this way, you won’t get stubborn remains and your microwave can always be quickly and easily cleaned.