Had a wonderful meal at Sacred Chow last night. It's creative, chowish vegan. They do Sunday brunch. Nice enough to take a client or a date.
The menu changes and has specials, but they post it online. , I loved the risotto, and the appetizer featuring a fresh marinara over eggplant rollatini was delicious.
Most people who have a reason to be at NYU for Shabbat knows that they can pre-pay a Shabbat meal, and the staff will guide you to the selections that are Shabbos-appropriate.
It is the only non-Shomer Shabbat veggie place in the city where I eat. There may be others that are trustworthy, but I don't know them. I eat at Sacred chow partly because the community trusts it, and partly I am very comfortable with the way the staff understands kashruth. Heres the teudah: http://sacredchow.com/kosher.htm
I thought I'd mention the place, because 'tis the season for a chowish vegan place.