That would be movie theater-style popcorn.
Many movie theaters shifted away from palm oil when there was some flak in the news about how unhealthy that stuff is. Palm oil is also what makes the best Ramen noodles so delicious (and unhealthy). They shifted to coconut oil back around the late 1980’s – but they may have shifted back since the media isn’t watching them any more. The seasoning they throw into the kettle is typically Flavocol: orange coloring, finely-ground salt, and a few other chemicals to preserve it for eons and/or make it all stick to the popped corn. A place like Smart & Final (or your local equivalent) that supplies restaurants and businesses will have it in stock. I still have part of a quart-sized container (smallest they had on sale) of the stuff that I bought in 1983 and it’s still tasty and well-preserved. A teaspoon of the stuff is good for about 10 gallons of popped corn. I also like to sprinkle the stuff on just-cooked french fries. 
For “herbed” popcorn, here’s another commercially-made popcorn secret:
[ol]
[li]*Fill a 10-gallon tin drum with 7 or 8 gallons of popped corn. [/li][li]Throw in a half-pint of herbed seasoning POWDER (taco, ranch, etc.)[/li][li]Cover the tin with its lid and strap or tape it down securely.[/li][li]#For 5 minutes, flip the tin end-over-end while spinning it at the same time.[/li][li]Set the tin upright for 2 minutes to let the dust settle.[/li][li]Open the lid CAREFULLY and dish out the seasoned corn.[/li][/ol]
The key, here, is that the flavored coatings must be in powder form. Taco, Ranch, and sour cream & onion seasonings can often be found in grocery stores in powder format already, but you can probably make your own from the spice aisle of your grocery store if you don’t find something in an envelope that suits your palate. Fresh basil (or parsley or sage – or rosemary or thyme for that matter) wouldn’t work because other powders would clump up around the wet leaves, but dried basil flakes or powder would do well and distribute nicely. I suspect it would be important for all of the herbs to be ground to the same consistency so they intermix properly for even distribution across the popcorn.
So, if you don’t happen to have a popcorn tin-flipping/spinning machine handy and/or you’re just not hungry enough to consume 8 gallons of popcorn and/or you just don’t want to be sick of that flavor by the end of the week, you will want to scale the equipment and recipe down somehow. I’d suggest something like a large stock pot, a paint-shaking machine%, bungee cords, and a lot less seasoning powder; I’ll leave it to better chefs and mathematicians to figure out the correct ratios as well as how to manually flip-and-spin the container at a consistent speed for 5 minutes. Once you’ve got those recalculations done, let us know here; I’ve got some Red Robin restaurant seasoning I thought I’d try on popcorn…
–G!
- There must be some emptiness in the container to let the powder and the popcorn tumble around each other. Too much space and the falling corn will break up from being abused too much; not enough and the powder won’t coat all the popcorn.
This is the hard part, and my boss had to invent a machine to do it.
% I jest. The violence of such a machine would wreck your popcorn.