try the one's that you can microwave they come in a variety of flavours [not tried them in a maker tho'] My guess would be that it's sprayed on afterwards
You mix the popped corn with the flavour or sweetener that you prefer and then warm in a pan. There's hundreds of products and recipes available. Type sweet+popcorn into your search engine, and the results will keep you happy for a long time. Good luck; it's really easy to do and the results are yummy.