Gather all the ingredients so you have everything at hand.
Making Dough
In a large mixing bowl, combine 320 g all-purpose flour, 240 g unsalted butter, 160 g sugar and 1/4 tsp. salt Mix all the ingredients using a hand mixer to help combine the butter into the dry ingredients.
Add 80 g roasted black sesame seeds and 2 egg yolk into the mixing bowl and mix again.
Put the dough on your work surface. Form it into a ball and divide into 2 equal portions. Roll each portion into a log approximately 2 inches (5 cm) in diameter.
Wrap the logs tightly in plastic wrap and refrigerate until firm, for at least 1 hour. You can add rice to help it keep its cylindrical shape.
Baking Cookies
Preheat the oven to 350°F (175°C). Remove the plastic wrap and cut the dough into discs about 1 cm thick. Place them on a baking sheet lined with parchment paper.
Bake for about 20 minutes or until lightly browned around the edges.
Serving
Allow to cool on the baking sheet for about 10 minutes. Then serve.