Line two baking sheets with parchment paper and set aside.
Preheat the oven to 350°F.
Make the dough
Cream the 1 cup butter and 2/3 cup white sugar together until pale and slightly fluffy.
Add the 2 egg yolks, one at a time, beating in between each.
Add the 1 teaspoon vanilla extract.
While mixing, add the ½ teaspoons salt and 2 1/3 cups all-purpose flour gradually until well incorporated.
Scoop, roll and fill
Using a small cookie scoop, scoop the dough into even sized balls and place on the baking sheets leaving space (about 2 inches) between each.
Using your thumb, make an indent into each cookie without pressing all the way to the bottom.
Spoon raspberry jam into each cookie.
Bake
Bake for 12-15 minutes. Cookies will be lightly browned underneath.
Remove from oven and cool for 10 minutes, then transfer to a wire rack to cool completely.
Video
Notes
How to storeStore in an airtight container in the refrigerator for up to a week.Substitutions/AdditionsYou can use any flavor jam you like. I use apricot, raspberry or strawberry jam, or lemon curd. After thanksgiving, I make Cranberry Thumbprints using leftover cranberry sauce.Freezing instructionsThis recipe can be frozen before baking. Scoop them onto a cookie sheet, and do the thumb imprint. Cover with plastic wrap, then freeze until solid then store in a Ziploc bag. When ready to bake, remove from freezer and place on cookie sheet.Fill with jam of your choice, and bake as usual, adding a few extra minutes on.