Directions

Pre-heat oven to 350° F

In a large bowl, sift together the flour, baking soda, and salt.

In the bowl of a stand mixer fitted with the paddle attachment, combine the butter and sugar and beat on medium speed, scraping the bowl occasionally, until light and fluffy, about 2 minutes. Add the egg and vanilla and beat until fully incorporated, about 1 minute. With the mixer on low, add the flour mixture, and stir until just combined. Shape the dough into a disc, wrap it in plastic, and chill at least 1 hour and up to 24 hours.

Roll the dough into 1-inch balls and arrange on baking sheets, leaving about 3 inches between cookies. Using your thumb or the round end of a small pestle, make a well in the center of each cookie. Using a teaspoon, fill each well with jam, being careful not to overfill the wells. Bake, switching the cookies between the upper and lower racks about halfway through baking, until golden, about 15 minutes.