Vapour Lock Issue

Oh,boy. Ok you need to prove it's a fuel issue. A 30 minute delay, could be a vent/vacuum problem, or an electrical issue, or a carb issue.
So, as inertia suggests, run with the gas cap loose. If the problem persists, pull over and immediately pop the air filter house off. Stare down the primary bores and pump the throttle a couple of times. Slow,long strokes, all the way back. You will be looking for a long continuous stream from the accelerator nozzles. If it's there, there is fuel in the bowls. Next will be a spark test.Sometimes the ECU,or the MAG trigger quits when it gets hot. I used to carry spares in the glove box for just such times.