Set the butter out to soften. Mix the sugar, flour, egg yolk, vanilla and salt into the butter. Once you have everything nicely mixed together, get about a teaspoon of the dough and roll it into a ball.
Preheat the oven to 350 degrees. Put the balls on an ungreased cookie sheet. Use your thumb to press a thumbprint into each unbaked cookie. Use a teaspoon to fill the thumbprint depression with the strawberry preserves.
Slide the cookie sheet into your oven and bake an average of 17-18 minutes. Keep your eyes on the cookies so you can get them baked to perfection in a little less or a little more time in the oven.
Set the cookies out on a linen cloth to cool. This will give you about two dozen. Eat all you want and put the rest into a covered container. You could also freeze these baked cookies for use at a later date.
Readers with questions or comments for Dave Kessler may write to him in care of this publication.