I accidentally put sachlav a milk drink into a meat microwave and it started to foam around 30-45 seconds into the microwave. The foam got on the microwave circle plate. Do I need to kosher the microwave? And if so how? Also would the din be different if the drink wasn’t hot enough to the touch that I would have to remove my finger from it?
The microwave has to be kashered. Wipe out all the surfaces in the microwave, including the plate, and make sure they are all clean. Then wait 24 hrs. and put a bowl of water inside it and boil it until the microwave fills with steam.
Pischei Halacha pg 234.