I'm not sure I know what a "hard part" looks like.

I don't have a particular *type* of scene that I hate (well, maybe red herrings, aka stuff-the-hero-tries-that-doesn't-work, but I'm getting better at it), but there are certainly times when the words flow easily, and other times when every word is like pulling teeth. And times when pulling teeth would be easy and painless by comparison.

Unless plot blurbs and other promotional/marketing type bits count?

LOL yes.