COMBINE ALL INGREDIENTS for the crepes, except the butter. Whisk well and pass through a fine strainer. Let rest 1 hour. Add butter before cooking the crepes. Cook the crepes and be careful not to brown them. Lay the crepe out on a piece of parchment or a clean towel (don''t lay out more than 12 at a time or they will dry out). Fill with a spoonful of caviar and sour cream.
Pull the edges of the crepes up to form small purses and tie with a chive. Serve warm or at room temperature, lightly brushed with butter. These crepes can also be rolled or folded in the more traditional manner if forming the purses seems like a daunting task. The result is beautiful, however, and worth the extra effort.
This elegant recipe comes from Katherine Alford, chief instructor at the New York Cooking School. Katherine used to be the chef at the Quilted Giraffe in New York. These crepes are a signature dish of that restaurant.