Preheat oven to 375° F. Line baking sheets with parchment paper or lightly grease.
Sift together flour, potato flour, baking powder and salt; set aside.
Soak the dates in the hot coffee for at least 30 minutes. Drain coffee but reserve 1 teaspoon of the liquid.
Cream butter and sugar in a mixture bowl until light and fluffy. Add the egg, milk, reserved coffee and vanilla and mix until blended.
Add soaked dates into the flour mixture and toss just to coat lightly. Add flour into the creamed mixture and mix until smooth.
Form approximately 2 tablespoons of dough into a ball by rolling between palms. Make an indentation in the center of each ball and place on prepared baking sheet at least 3" apart. Fill each indentation with 1/2 teaspoon of orange marmalade.
Bake cookies in preheated oven for 12 to 15 minutes or until lightly golden. Cool thoroughly on racks before serving.
Garnish with orange peel or a stick of cinnamon.Makes 8 Source: