• Gather all the ingredients.
  
• In a large bowl, using a handheld mixer or a stand mixer fitted with a paddle attachment, beat the butter for 30 seconds.
  
• Add ½ cup sugar and 2 Tbsp miso.
  
• Beat everything together on medium-high speed until smooth, light, and fluffy, about 2 minutes.
  
• Crack the egg and whisk in a small bowl. Gradually add the egg to the butter mixture while mixing.
  
• Beat on high speed until combined, about 1 minute. Scrape down the sides and up the bottom of the bowl and beat again as needed to combine in between.
  
• In a small bowl, combine 1 ⅔ cup all-purpose flour and 1 tsp baking powder and mix with a fork (I do this extra step so that baking powder is evenly distributed when sifting).
  
• With a fine-mesh sieve, sift the flour mixture over a medium bowl.
  
• Gradually add the flour mixture into the mixing bowl at low speed.
  
• Once you finish adding all the flour mixture, turn up to high speed and beat until incorporated.
  
• Sprinkle a small amount of flour on the working surface and transfer the dough. If the dough is too soft, chill in the refrigerator for 15 minutes. By chilling, the butter/fat will solidify and it'll be easier to work with.
  
• Roll the dough into a ball and cut in half.Note:This recipe can be used for cut out cookies. Form the dough into a disk, wrap and chill then roll out to ¼-½ inch, cut and bake.
  
• Roll the dough into 2 long logs.
  
• Each log should be 10 inches (25 cm) long with 1 inch (2.5 cm) diameter.
  
• Cut the long logs in half; now you have four 5-inch (12.5 cm) logs.
  
• Prepare a small flat container (or baking sheet) and add white sesame seeds (save the black one for later a time). Moist a sheet of paper towel with water and wrap around a log so the dough is moistened.
  
• Roll the moistened log in the sesame seeds and wrap in parchment paper or plastic.
  
• I've learned the best way to keep the dough from flattening out on the bottom is to place the dough on rice.
  
• 把其他2日志在黑色的芝麻d wrap in parchment paper or plastic.
  
• Chill the cookie dough in the refrigerator forat least 30 minutes. Meanwhile,preheat oven to 350°F (180°C). For a convection oven, reduce cooking temperature by 25ºF (15ºC). Prepare a baking sheet lined with parchment paper.
  
• Once the dough is chilled, use a sharp knife to cut dough into 8 slices of even thickness.
  
• Cut the rest of the cookie dough and transfer to the baking sheet lined with parchment paper. If the dough is no longer chilled, you can put the baking sheet in the refrigerator for 15 minutes until the cookies are chilled and firm.Tip:如果饼干面团冷冻,他们不会做伴奏letely lose their shape.
  
• Bake the chilled cookies for 20-22 minutes or until lightly browned on the edges.
  
• Remove from the oven and allow to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
  

To Store:

• These cookies stay fresh in an airtight container at room temperature for up to 1 week. I usually reheat the cookies at 350ºF (180ºC) in the toaster oven (or oven) until toasty.To freeze the dough:Tightly wrap the logs in plastic wrap and put them into freezer bags. Freeze for up to 3 months. Let them thaw in the refrigerator for 2 hours before slicing.