It is hard to find good Indian food in Dallas, but  can highly recommend MUMTAZ in Richardson.  This family has been in the Indian food business for 25 years and used to own Taj Mahal in North Dallas (no more, and it shows btw) but have recently reopened in Richardson at MUMTAZ.  It is absolutely wonderful-- authentic, spicy, a wonderful Tandoori grill and a nice wine list!  Your water glass will be kept full, as well.  The service is lovely, the food is wonderful, the prices are very reasonable.   MUMTAZ rivals that of any city.  But it is unparalleled in Dallas, not dumbed down for American taste, it is truly authentic.  MUMTAZ-- Enjoy!