Heat the oven to 375°F. Use an electric mixer to cream together the butter and jaggery. Add the vanilla and egg and beat until well blended.
Combine the flour, baking powder, spices, and salt in a bowl. Add half the dry ingredients to the dough, beat until incorporated, then add the milk. Beat for 10 seconds, then add the remaining dry ingredients.
Drop tablespoon-sized mounds of dough about 3 inches apart on ungreased baking sheets. Bake for about 12 minutes, until the edges are browned. Cool for 2 minutes on the baking sheets before transferring to a cooling rack.
Store in a tightly covered container at room temperature for a couple days.