I'm REALLY going to date myself ha ha because I was cooking those things before microwave ovens were around.
Back then they came in a metal container. I would thaw them and then stick them in a 350 or so oven until they were bubbly - with foil on top so the top wouldn't burn.
I would probably put the frozen thing into a small covered oven safe dish like Pyrex - thaw in the refrigerator - and then cook as above.
Some days I pray for Silence, Some days I pray for Soul,
Some days I just pray to the God of Sex and Drums and Rock 'N' Roll.