- 4 oz. (1 stick) unsalted butter, softened
- 1/4 C. sugar
- 1/8 tsp. salt
- Finely grated zest of 1 orange (optional)
- 1/2 tsp. vanilla extract
- 1 large egg yolk
- 1 C. all-purpose flour
- Raspberry and/or apricot jam
Preheat oven to 325 degrees F.
With an electric mixer, beat butter, sugar, salt, orange zest and vanilla until well combined. Do not overmix. Beat in yolk. Sift the flour and add into the mixture until just combined. Scrape the bowl and mix again. Turn dough onto work surface and knead together until smooth.
On a lightly floured surface, press the dough into a 1/2-inch thick patty. Dip a 1-inch round cutter into flour and cut out circles. Place cookies on an ungreased baking sheet at least 1 inch apart. Gather up scraps, form another patty and repeat until all the dough is used up.
Using your thumb or the end of a large wooden spoon, make an impression in the center of each cookie without going through. Fill each impression with about 1/4 tsp. jam.
Bake for 22 minutes or just until the jam bubbles. Let the cookies cool on a baking sheet for 20 minutes, then cool completely on wire rack.