My method, maybe could help

Heat always at the absolute bottom of the cap.

Heat at least 2 seconds past the 2nd click (each herb reacts differently, I had outdoor Blackjack which was able to give me the biggest clouds ever and you can heat it a lot, but if it's too dry, you can combust if you go past the 2 seconds

I'm always doing only 1 heating cycle for extracting it all, so after I insert dynavap into a water pipe, I'm using my torch to keep the temp, but you really have to get used to it. Some combustion will happen if you will be greedy for just massive hit.

And single torch flame should be the best for controlling the temperature while drawing