Vegetable Biryani for a Crowd

B-I-R-Y-A-N-I. The very word conjures up images of a dish that is rich and exotic, redolent with spices and packed with "good eats". And so it is, a layered rice dish of Persian descent, introduced to India via Mughal cuisine. When I was growing up, Chicken Biryani was my Mom's specialty, a labor of love that took her all of Sunday morning to prepare and resulted in a delicious and heavy Sunday