Preheat oven to 350 degrees Fahrenheit.
Lightly roast the almonds for 5-8 minutes and allow to cool, then chop to a coarse or fine consistency, depending on preference.*
Sift together the flour, baking soda, and cream of tartar in a medium bowl. Set aside.
Add butter to the bowl of a stand mixer with the paddle attachment equipped. Beat on medium-high speed for 10 minutes; it will appear light and fluffy. Reduce the speed and add in the sifted powdered sugar. Once it’s incorporated, increase the speed to medium-high and beat an additional 10 minutes; it will then appear fluffier and lighter in color (this is an important step – see notes for more info).*
Reduce the speed to medium-low and add the eggs one at a time, then add the vanilla and brandy or ouzo and mix until incorporated.
Add the sifted flour in half-cup increments. Once all the flour has been added, add the almonds. Increase the speed to medium-high and beat for 30 seconds.
The dough should feel soft and silky with a pillowy texture. If it sticks to your hands, continue mixing and add sifted flour in two tablespoon increments until it no longer sticks.
Roll the dough into walnut-sized balls (26-30 grams or two tablespoons) and flatten slightly and/or shape into crescents. Place onto ungreased baking sheets one inch apart.
Bake for 20-25 minutes or until they reach a pale beige/golden color on top; the bottoms will be golden brown. Note that the cookies are extra delicate when they’re hot, so handle with care.
Remove from oven and let cool for five minutes. An optional step is to sprinkle the kourabiedes with rose or orange blossom water.
With a sieve, evenly line a large pan with 1 ½ cups powdered sugar. Carefully nestle the kourabiedes into the sugared pan and completely cover with 2 cups of sugar. Use more sugar if needed.
Allow to cool completely before transferring to a platter to serve.