That was probably hot carbon deposits inside the cylinder causing ignition of the mixture. A hot bulb engine, I think it would be possible to replace the plug with a hollow chamber containing wire coils which would remain hot while the engine was running, but would probably need 5 minutes with a blowlamp to start.
There was a clever Honda 2 stroke a few years ago that actually deliberately blew hot exhaust back into the barrel. The double cooking cleaned the emissions, I think, and the hot gas also replaced the spark plug. I think.
I'll see what I can find. A non spark engine may need a spark to start it, and then run happily just using the Honda system.