Sift flour, soda, salt, nutmeg and powder in a bowl.
In separate bowl cream the butter and sugar (use cookie paddles or dough hook this will get thick)
Add the egg and beat again
then add the vanilla and sour cream and beat it smooth
Mix in dry ingredients and beat smooth - it will be thick.
wrap up in wax paper or parchment paper and chill in fridge for 3-4 hours
preheat oven to 350
roll out to 1/4 inch cut into rectangles about 1 1/2 inches x 5 inches
bake for 12 mins, until the edges get a slight golden color to them (don't over bake) let cool
Royal Icing
In a mixer mix the powdered sugar and meringue powder, then add the water
beat for 7-10 mins on medium speed, until it's smooth and glossy
Separate into two bowls, one with about 4 C and one with 1/2 C in the other
place plastic wrap down on top, touching the frosting, so it doesn't dry out
Decorating
Dye the larger bowl of royal icing yellow
in a piping bag with a number 4 tip pipe a rectangle outline on each cookie
thin down the royal icing with a little water (do a 1/4 tsp at a time), when you mix it it should smooth out again at the count of 10 (don't add too much)
pipe the runnier icing into the outline and shake smooth, using a sharp pin if needed to pop bubbles or move the icing around a little
let crust and dry
Take the 1/2 C of icing and add a little bit of cocoa powder, like 1 tsp, stir smooth, then add some black powder or gel dye, until your happy with the color.
if it's too thick add a little bit of water, like a few DROPS at a time until it will pipe smoothly from a tip 3 or 4
add plastic wrap down the center of the cookie to use as a guide and then pipe the short lines, in groups of 4 down the side of the ruler
moving the plastic wrap back add the longer lines between the shorter groups of 4