4ouncesunsalted butter, softened but still cool, (1 stick)
1/3cupsugar, plus extra for sprinkling the cookies
1 1/2teaspoonsmatcha powder
Position racks in the upper and lower thirds of your oven and preheat to 350º. Line two cookie sheets with parchment paper.
In the bowl of a kitchen aid fitted with the paddle attachment, cream together the butter and sugar until smooth, creamy and well combined, a few minutes on medium-low. (This is a dough that you don't want to over-aerate, or the dough will be difficult to roll and the cookies will spread too much during baking.) Beat in the salt and matcha, then add the flour, mixing on low until barely combined. Add the cocoa nibs.
Use a plastic scraper to fold the dough a few times by hand to make sure it is homogeneous, then form into a disc on a piece of parchment or plastic wrap. Chill until mostly firm, 30 minutes to an hour.
Roll the dough out to about a 1/6" thick round. This is most easily done between two sheets of parchment paper and light dustings of flour as needed. (If the dough becomes at all sticky, return to the fridge for 5 or 10 minutes.) Cut with a 1 1/2 - 2" round cutter, cutting the rounds as close together as possible. (You can either press the scraps back together and repeat the rolling/cutting process, or be lazy and just bake off the scraps to snack on.) Place the rounds on the parchmented baking sheets, spacing them 1" apart, and sprinkle with a bit of sugar.
Bake the cookies until lightly golden, about 15 minutes, rotating front to back and top to bottom halfway through. Cool on racks.
Store the cookies in an airtight container for up to a week.
Nutritional values are based on one of twenty four cookies.