I work in an office in the PATH. There are days where you just need an afternoon pick me up but you don't want to bus the waistline.
Dekefir is a great place to satisfy your sweet tooth but still get nutrients! They have a range of items to choose from, from frozen Kefir with a wide range of toppings, smoothies, and breakfast bowls. I usually get the single serving of the frozen Kefir. Its not too sweet, and has a really good tang to it. If you want to sweeten it up, there are different toppings to choose from. The ones that I've chose that I like are: any fruit based ones, toastes sesame walnut (must), chocolate chip (not so crazy), and granola.
The service is great, they are quick and you can get your treat and eat it on the way back to the office.
Make sure to get a Stamp Card, as the incentives include free toppings and eventually free yogurt!