Cream together butter and sugar until smooth and lightened.

Sift together flour and baking powder; add to the butter mixture.

Incorporate egg, milk, spices, salt, and orange zest into the dough until just combined.

Divide the dough into two portions.

Roll each portion between parchment paper into 1/8 inch thick rectangles.

Refrigerate the dough for at least 1 hour, or preferably overnight.

Preheat oven to 375 degrees Fahrenheit.

Line baking sheets with parchment paper.

Cut the chilled dough into 1 1/2-inch squares.

Place cookies on baking sheets, spacing them 1 inch apart.

Bake for 10-12 minutes, or until evenly browned.

Cool on baking sheet for 2 minutes, then transfer to a wire rack to cool completely.

Microwave chocolate in short intervals until melted and smooth, being careful not to overheat.

Dip cookies in melted chocolate.

Place chocolate-dipped cookies on waxed paper to set.