Pecan Thumbprint Cookies

Ingredients (9)

• 1/2 cup butter, softened
• 1/4 cup packed brown sugar
• 1 large egg yolk
• 1/2 teaspoon vanilla extract
• 1 cup all-purpose flour
• 1/4 teaspoon salt
• 1 large egg white, lightly beaten
• 3/4 cup finely chopped pecans or walnuts
• 1/2 cup preserves or jelly of your choice