Single LED candle with FastLED

Hi all,

I'm searching for some help to make a (tea)candle-effect with one single LED with using FastLED.

Since I'm using a single RGBW WS2812B LED, it's a bit more difficult to find nice examples online.

Does anyone know if there is any example availabe(the fire 2012 examples is really ugly...)
Or else, how should I code this.. I also would be happy to generate some code colours and make them flicker..

Very important; I don't want to use delay() since my code has to do some more things.