Walnut Thumbprints

1/2 cup butter or margarine, softened
1 cup packed brown sugar
1 egg
1 teaspoon vanilla extract
1-3/4 cups all-purpose flour
1/2 teaspoon baking soda
1/4 teaspoon salt

Filling:
1 cup chopped walnuts
1/2 cup packed brown sugar
1/4 cup sour cream

In a mixing bowl, cream the butter and brown sugar. Beat in egg and vanilla. Combine flour, baking soda and salt; gradually add to the creamed mixture. Refrigerate for 30 minutes. Roll into 1-in. balls. Place 2 in. apart on greased baking sheets.

Using the end of a wooden spoon handle, make an indentation in the center of each ball. Combine filling ingredients; spoon about 1 teaspoonful into each cookie.

Bake at 350° for 11-13 minutes or until lightly browned. Cool for 5 minutes before removing to wire racks. Makes about 3 dozen.