Sukhjinder Singh has a new feather to place in his growing cap as as restaurateur: His latest venture, Spice of India(10633 Page Avenue, 618-225-7838) is now open in north-central St. Louis County, just west of the intersection of Page and Ashby. Singh's third area restaurant follows his successes Aroma Indian Grill in Hazelwood and Taj Indian Cuisine in Edwardsville, Illinois.…