Random thoughts here...
When I start out, I have a great plan for the beginning of the story, and I figure that I'll just find the rest as I go - or brainstorm and outline one chapter at a time - but then I get to the next chapter, and I find out I have no idea what to do next, or even how I want the story to end.
It sounds like you are a "Pantser" -- a writer who writes by the seat of the pants. This is opposed to a Plotter, who has an outline, timeline, storyboard, whatever to act as a roadmap. Neither is right or wrong. It's whatever works for you. I usually have notes scribbled all over a piece of paper with some notes on each character, a scene idea or two, maybe a snappy line of dialogue that's popped into my mind and ideas for a location. The method that works for you is the "right" one.
If you have a story that you think needs fleshing out, then I would suggest you look for places where you're telling the readers something and try to show them instead.
Excellent suggestion! And one I struggle with myself. Showing involves strong verbs and dialogue. That example of Clark making all the sandwiches a perfect example of showing and not telling. One rule of thumb I've read is if you can get the information across in dialogue rather than narrative, do it.
Well, the first thing I would say is that I hope you're not underestimating the value of a "great vignette."
Amen to that! I just took an old vignette, reworked it and sold it to a magazine. And that brings me to my next point.
In fanfiction, the characters and universe are already created for you. You don't have to explain who they are, what they do for a living, what they look like, what their backstory is, et cetera. That takes up a lot of page count in original fiction. So your fanfic may be a little shorter simply because you didn't have to create your own universe and characters.
ML gave some good examples of finding plot ideas. I keep a folder of interesting articles I see in the local paper or even on Internet news sites. Most recently was about a jilted bride who used her non-refundable reception as a fundraiser for a children's charity. That little news item is the basis for a story I'm working on now.
Also, ask "What if?"
Just my two cents. Hope it helps.
