Preheat oven to 375°F. In a medium sized bowl (or bowl of a stand mixer) cream butter, sugar and egg together until light and fluffy.
Sift flour, baking powder, salt, ginger, cinnamon, cloves and nutmeg together and add to butter mixture stirring just until combined. Stir in chopped pecans.
Roll dough into 1-inch balls, and place on a baking sheet. Top each cookie with a pecan half (domed side up), pressing slightly into cookie. Bake for 8-10 minutes.
Let cool for a few minutes before transferring to wire rack to cool completely.