Begin by browning the butter. Add 8 ounces of unsalted butter to saute pan and warm it over a medium heat. The key to browning butter is keeping an eye on it and removing it from the heat source once it browns. If you haven’t done this before, here is a great tutorial on browning butter.
Now, I would normally do this in my stand mixer but I really wanted to show you these steps. Add the browned butter along with the 1/4 cup sugar and 1 cup brown sugar to a large mixing bowl. Mix it well, until all of the sugar has fully combined with the butter.
Now whisk together the egg and the 2 egg yolks. The reason I am using more yolks than whole eggs is that egg whites dry out baked goods. Sometimes this is desirable. For these cookies, I wanted them to be moist (that word gives me the creeps) and decadent. Add the whisked eggs to the butter and sugar mixture, mixing to combine.
Now add in 2 teaspoons of vanilla extract (the rest is for the icing) and 1/3 cup La Tourangelle walnut oil. Make sure to thoroughly mix in the ingredients.
Sift together the 2 1/2 cups bread flour, 1 1/4 teaspoon salt, and 1/2 teaspoon baking soda. I am using bread flour because it is built for moisture, more so than all purpose flour. I want to take advantage of all those glutens! Here is a great explainer on flours. Now work the flour into the wet mixture but don’t over work it. You just want it to be combined.
Fold in 1/3 cup of chopped walnuts. Once worked in, cover the dough and let it chill for about an hour.
Preheat the oven to 375° F and place the racks in the middle of the oven.
While the oven comes to temperature, roll out the cookies and place them on a large baking sheet lined with parchment paper. Make sure to give them enough room to spread out during baking. Bake the cookies for about 15 minutes, or until the edges just start to brown.
While they bake, sift 1 cup of powdered sugar into a large mixing bowl and mix in 1/4 teaspoon of vanilla extract and 2 tablespoons of bourbon. Now add in 1 tablespoon of the milk and add more until desired consistency is reached. You shouldn’t need more than 2 tablespoons total.
When the cookies are finished baking, remove them from the oven and transfer them to a cooling rack. Let them fully cool before icing them.
I suggest placing them on parchment paper, add the icing to a sandwich bag, cut one of the corners, and then drizzle the icing over the cookies. It’s the easiest way and don’t they look good?