I had thought that already prepared chicken soup (which was in a throwaway plastic container) was actually parve soup, and reheated it in a parve stainless pot, and then poured it into two milchig glass cups, and then added cold milk!! Could I kasher the pot with boiling water? What about the cups? I had also used a parve stainless spoon to stir the soup a couple of times in the parve pot. What to do about spoon. Can I kasher it?
You can kasher the pot spoon and glasses. Wait 24 hours from when the pot etc. became trief, make sure they are all totally clean, even by the handle of the pot, etc, either stick the pot etc. into a pot of boiling water, wait keep it inside for a few seconds so that the pot returns to a boil, and then wash them off with cold water.
Although it is controversial if glass can be kashered, however here since the glass cups were only iruy kli rishon, numerous poskim that are stringent by glass would agree that since it isn’t actual a kli rishon that it can be kashered.