Preheat oven to 350°F.
In a medium bowl, combine flour, baking soda and spices.
In a mixing bowl, beat butter and brown sugar until fluffy.
Mix in molasses.
Beat in egg and vanilla.
On low speed, slowly add dry ingredients.
Roll dough into 1-inch balls and place on a cookie sheet 1 ½ inches apart. These cookies do not spread a lot.
Bake for 15 minutes at 350°F.
Transfer to a wire rack to cool.
In a small mixing bowl, whisk the ingredients for the glaze together.
Place wire rack on a rimmed cookie sheet or parchment paper. Dip the cookies into the glaze and return to the wire rack to allow the glaze to dry.
Store in an airtight container with a piece of parchment paper between the layers.
If you freeze these cookies, allow them to defrost completely before serving. The glaze will look wet as they defrost, but it will dry again when thawed.