HOW TO MAKE IT :
- Preheat oven to 350°F.
- In a medium bowl, cream together butter and granulated sugar until smooth.
- Mix in lemon zest, egg yolk, and flour until dough comes together.
- Chill dough for 15-30 minutes.
- Roll dough into 1 1/2 inch balls and place on a cookie sheet lined with parchment paper.
- Using a spoon, make a small impression in the center of each ball. Fill each impression with the blueberry jam.
- Bake for 10-12 minutes.
- While the cookies are baking, mix together confectioners’ sugar, lemon juice, and milk in a medium bowl until smooth. Drizzle over warm cookies.
