A single lamp is usually more efficient (in terms of lumens per watt). That is, one lamp has more luminous output than multiple lamps adding up to the same wattage.

This is especially true for incandescents, but it's also true for fluorescent, and I expect for LED lighting too.

I don't see any advantage for the recessed light over a pendant, but of course that's up to you.

davidr - thank you!! Also, thanks for the input about the pendant, I assumed because the can light would be up higher that it would light the area better than the pendant that is hanging further down. But then again the light would have to travel farther. I also considered a flush mount fixture that would give me 100W or equivalent depending on the light source. But maybe I don't need that much light over the sink. Any suggestions? Thanks again.

Most pendants, at least those with translucent globes, produce some indirect light. This is light reflected off surfaces above and around you. It fills in the shadows so your lighting is more even.

OTOH, recessed lights have no indirect component, so they produce stronger, darker shadows. How objectionable this is depends on the exact location of the light relative to where you do your work.

As for the amount of light, it really depends on your needs. As I get older I find that I need more light. That said, currently I have a 15 watt fluorescent light (equivalent to a 60 watt incandescent) over my sink. That seems to be plenty, as long as the other lights in the kitchen are on. Others might want more.