Prepare the flavour mix by mixing together the first 5 ingredients in a small bowl. Use the back of a spoon to crush any particularly large nutritional yeast flakes into a finer powder.
In a large pan (the larger, the better) place the oil and 3-4 popcorn kernels and cover with the lid.
Turn the heat on to medium-high and wait for the first kernel to pop. Be patient! Once this happens, add the rest of the kernels and cover again.
Hover the pan over the heat and with one hand supporting the side and another on the lid, shake the pan to prevent burning. Every now and then, remove the lid partly to allow steam to escape. Keep shaking until popping slows to one kernel every 2-3 seconds, then remove from the heat.
Transfer the popped corn to a large bowl and toss in the flavour mix. Serve hot.