Cream the butter and brown sugar together in a large mixing bowl. Add the egg, the ginger and the lemon zest. Beat well.

In a second bowl, measure the flour, baking powder and ground spices. Gradually add to the butter and eggs to make a dough.

Turn the dough out onto the counter and pat into a disk, or a log if preferred. Wrap the disk with baking paper and foil, and let chill for a couple hours or overnight. At this point the dough can be divided and frozen for later if desired.

To bake, preheat the oven to 350°F/180°C. Measure baking paper to fit your trays.

Portion the dough and roll it into balls about 1" in diameter. Place a piece of baking paper over top of the ball, then press the ball into a thin round using a heavy flat bottomed cup.

Sprinkle the rounds with a little sugar before baking for 8 - 10 minutes. Longer cooking time yields a crispier cookie.

Cool on a rack.