small white or silver candy balls or coarse
PREHEAT oven to 350F. Line 2 large baking sheets with parchment. Fit a large pastry bag with a #9 or large open-star tip. Sift flour with matcha in a medium bowl.
BEAT butter, sugar and salt in a large bowl, using an electric mixer on medium-high, until fluffy. Beat in egg. Reduce speed to low and gradually beat in flour mixture until just combined. Dough will be firm.
SPOON batter into pastry bag. Pipe into large shell shapes (1 ¼ in. wide) 1 in. apart on prepared sheets by squeezing hard and letting the batter fan out before pulling the bag toward you to form a point. Refrigerate for 10 to 15 min.
BAKE until tops of cookies are firm, 15 to 18 min. Cool on sheets for 5 min. Transfer to a rack to cool completely. Repeat.
MELT chocolate in microwave-safe bowl on medium, stirring every 20 sec, until completely melted and smooth. Dip the point of each cookie in chocolate, shaking off excess on edge of bowl. Place on parchment-lined sheet and sprinkle candy balls over chocolate. Refrigerate until chocolate is firm, 30 min. Store cookies in an airtight container for up to 1 week or freeze for up to 1 month.