With the rack in the middle position, preheat the oven to 350°F (180°C). Line a baking sheet with a silicone mat or parchment paper.
In a bowl, combine the flour, matcha and salt.
In another bowl, cream the butter and sugar with an electric mixer for 1 minute. Add the egg and vanilla. Mix until smooth. With the machine on low speed, or with a wooden spoon, stir in the dry ingredients.
Transfer the dough to a pastry bag fitted with a 1/2-inch (1 cm) star tip. On the baking sheet, form the cookies by piping a series of four dots in a line, each dot about 1/2 inch (1.5 cm) in diameter, letting the four dots touch one another.
Bake for 16 minutes or until the edges of the cookies are lightly golden. Let cool completely.
Using a small spoon, cover the tip of each cookie with the melted white chocolate and top with the sprinkles, varying the colours, if desired
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.