Preheat your oven to 325°F and line a baking sheet with parchment paper. Set aside.
In a large mixing bowl or using a stand mixer with a paddle attachment, cream together the butter, granulated sugar and confectioners until light and fluffy. This step is crucial for a soft, melt-in-your-mouth texture. Don't rush it!
8 tablespoon unsalted butter, ¼ cup white sugar, ⅓ cup confectioners' sugar
Add the egg yolk, vanilla extract, and salt to the mixture, beating until well combined.
1 egg yolk, 1 teaspoon pure vanilla extract, ⅛ teaspoon salt
Mix in the flour until just combined.
1 ¼ cups all purpose flour
Scoop out portions of dough (about 1 ½ tablespoons each) and roll them into balls. Roll each ball in granulated sugar and place them on the prepared baking sheet, leaving space between each.
¼ cup white sugar
Use your thumb or the back of a teaspoon to make a deep well in the center of each ball. Be careful not to make it too wide.
Spoon 1 teaspoon of raspberry jam into each well.
13 teaspoons raspberry jam
Bake for 10-15 minutes, then let the cookies cool on the baking sheet for at least 10 minutes before serving. Optional: dust with more confectioner’s sugar if desired. Enjoy!