There was a thread a couple weeks ago about how to change a ceiling box to accomodate an LED recessed light that you can just mount to a round 4" ceiling box. Poster had a problem, because there was a clearance problem with his particular existing box.
Anyhow, I was at HD this AM and as I was walking by, they had that fixture on display at the end of the aisle. They showed it mounted to one of those 4" ceiling boxes with a metal bar so that you can position the box between joists in the ceiling. As we already figured out, it's not really a true recessed light. It sticks out about
2" from the ceiling. But it does mount directly to the 4" box. I couldn't see the backside, how far in to the box it goes, etc, because other than the display one they didn't have any to sell so I could take a look. But for $25 it looks like a good solution for certain spots, like over the kitchen sink, which is where the OP was gonna put his.