Buttery soft and crispy cookies using only a few ingredients. These cookies are perfect for office snacks or holiday dessert table.
Position rack in the middle of the oven. Preheat oven to 350 degrees F and line 2 baking tray with parchment paper.
In a bowl of a stand mixer, place cubed butter and salt. Mix on low speed for 20 seconds.
Slowly add in sugar, vanilla extract and turn the speed to medium high. Beat until light and fluffy, and the butter is turning yellow-ish color, about 2 minutes. Use a spatula to scrape down the sides as needed.
Divide the egg whites into 3 equal portions. Slowly add in egg whites and beat well.
Slowly add in flour, mix on medium speed until dough is mixed, about 1 minute.
Scrape the dough into a ziplock bag or a large piping bag. Cut the tip of the bag about 1" to 1 1/2 " or use any desired tip. Chill in the fridge for 30 minutes.
Pipe the tip onto parchment paper, creating long waves, at least 2 inches apart from each other.
Bake for 6 minutes on the middle rack. After 6 minutes, rotate the tray and bake for an additional 4 minutes on the top rack of the oven.
Cool on baking sheets for 3 minutes and transfer to cooling rack to cool completely.
Depending on the heat of the oven, it might take longer or shorter time. You know the cookies are ready when the edges are turning light brown and the center looked underbake. This is ok.