Leaf is another restaurant that I was introduced to via the 2008 Denver Vegfest. I believe they had seitan skewers for samples and I went back to their booth over and over again. I finally got to try the actual restaurant recently, as I selected it as my restaurant to provide me with proper nutrition prior to attending a Hanson show.
The restaurant in itself is a sight to see. Giant windows line the street side of the restaurant and they were all open on the day I ate there, combining the best of eating inside and outside. Additionally, Leaf has a happy hour, three to six. For me, this meant my sandwich was $8 inside of $8.50, but appetizers and martinis are around $4 during this time- definitely something to consider.
I wound up ordering the blackened tofu and veggie sandwich with a side salad. This normally comes with cheese, but I asked them to leave it off and didn't miss it at all. The tofu was spicier than I expected but the cooling hummus and vegetables countered it nicely. Additionally, the house side salad was made memorable with the addition of dried cherries and banana chips.
Overall, I would eat at Leaf based only on how gorgeous the restaurant is but knowing that the food is delicious is also a plus. Leaf is located right off the Pearl Street Mall, so keep it in mind as the perfect break during a day of shopping.