Cream together the butter and sugar with a mixer. Mix the egg and almond extract to the butter and sugar.
In a separate bowl, sift the flour and baking powder together. Mix the flour mixture into the wet ingredients a half a cup at a time. Add the salt when half the flour has been mixed into the dough.
When the flour is completely incorporated, use a 1-inch scoop to make the cookies. Place on a parchment-lined cookie sheet. Then flatten with the bottom of a greased glass.
Bake at 375° for 8 minutes. The cookies will be very light-colored. Let set on cookie sheet for five minutes before transferring to a cooling rack.
While the cookies cool, make the icing by combining all three ingredients. Then spoon the icing on each cookie and use the back of the spoon to spread the icing out.