Cream together the softened butter and sugar, then beat in the egg and add the whole milk.
Grind the toasted black sesame into a fine powder.
Sift in the all-purpose flour, salt, and baking powder with the ground black sesame.
Combine the dry and wet mixes to form a dough.
Refrigerate the dough for at least 30 minutes.
Roll the dough into about ¾-inch balls and stamp them down into flat discs using a floured whiskey glass.
Carve rune symbols into the discs using a cheese knife.
Bake in an oven preheated to 350 degrees F for about 13-15 minutes.
