These buttery, crumbly yet tender shortbread thumbprints are filled with a lemon glaze that's tinted a lovely shade of pink with a single crushed raspberry. Enjoy a few with a cup of tea -- or a tall glass of their namesake refreshment.
Preheat oven to 325 degrees. Whisk together flour, 1/2 cup confectioners' sugar, and salt in a bowl. In a large bowl, beat butter with 1/4 cup confectioners' sugar, zest, and 2 tablespoons lemon juice on medium speed until pale and fluffy, about 3 minutes. Beat in flour mixture on low speed.
Roll dough into 1-inch balls. Transfer to parchment-lined baking sheets, 2 inches apart. Freeze 10 minutes.
Bake 10 minutes. Remove sheets one at a time and press the end of a wooden-spoon handle into center of each ball to indent. Continue to bake until golden on bottoms, 16 to 18 minutes more. Let cool completely on sheets on wire racks.
Whisk together remaining 1 1/4 cups confectioners' sugar and 2 tablespoons lemon juice with raspberry in a bowl, breaking up berry. Dust cookies with sugar, spoon glaze into indents, and let set, 10 minutes. Cookies can be stored in a single layer at room temperature up to 1 week.