These cookies are fun and simple to make. The dough is a very basic one: butter, sugar, flour, plus an egg yolk and some salt. The jam is your choice; any type would work well.There are two stages of baking: the first is to set the dough, the second much shorter stint sets the jam.
1 cup butter, soft
2/3 cup sugar
1 large egg yolk
1 tsp vanilla
2 1/4 cups flour
1/2 tsp salt
about 1 cup jam of choice
Preheat oven to 375F.
Beat together butter and sugar with an electric mixer on medium-high speed until light and fluffy, about 2 to 3 minutes.
Beat in egg yolks and vanilla extract.
Add flour and salt and mix until incorporated and dough comes together in a ball.
Form dough into 1-inch balls and arrange on prepared baking sheet.
Flatten balls slightly with your thumb or the back of a small spoon, leaving an indentation in the center.
Bake cookies for 8 to 10 minutes or until bottoms are just barely golden. Remove baking sheet from oven.
If indentations look shallow, further define them with the back of a spoon and then fill each with approximately 1/2 teaspoon jam.
Bake for an additional 3 to 4 minutes, or until jam melts slightly and edges of cookies are lightly golden. Transfer cookies to wire racks to cool.