I know someone who has a bbq place in a small town, and he does catering with it. Most of it is bbq, but he's personally a foodie and he does some very adventurous high-end menus for special events. It's nothing he advertises, but if you know who to ask...
His is legit since he's a food business already, but it feels like there's room for a similar but underground vibe.
Here's an edit just for you. Better?
I read this the other day and completely fell in love. What a fantastic thing to be doing - but, as jaysonelliot says, from the perspective of the person running the unofficial restaurant. It's worth noting that by the end of the article, he's opening a real restaurant. This was his way in, and it was very effective, probably because his enjoyment of his work shone through.
I wonder, though, if the same trick could be repeated by creating an unofficial restaurant aimed at diners who like good food but wouldn't think of trying to get into a fancy restaurant, or paying for one. Could you arrive from outside the restaurant "scene" and make a name for yourself in the same way?
Meanwhile, the movie Jiro Dreams of Sushi is on a related topic, and very good.
Do what you love.
I wonder, though, if it could be done with something more accessible - hacking not into high end dining, but changing the idea of what a restaurant is for the folks who like good food but wouldn't think of trying to get a top-tier table, or paying for one.
Meanwhile, if you're hungry for more food obsession (and entrepreneurial obsession, to a lesser degree), the movie Jiro Dreams of Sushi is worth a watch.