broken exhaust stud removal

I'm curious what heat you used?

I recently had an experience with this. Putting headers on, buddy snapped the back stud inside the head. Ok drill it out and gets an extractor. Snapped the extractor inside the head. Well ****. Get out the drill again, go buy a fancy carbide bit. Drill out the extractor. Use a different extractor. Rounded it off first go.

Ended up having to go the exhaust shop since we didn't have access to heat to get it out. Took the shop 6 hours with their oxy torch to burn it out and get it re-studded and going. Pain in the *** right there.