Preheat oven to 300 degrees. Beat powdered sugar and butter until lightand fluffy. Add vanilla and egg. Blend well. Stir in flour, poppy seedsand salt. Mix well. Drop dough by rounded teaspoonfuls 1 inch apart onungreased cookie sheets. With finger, make an indentation in center of each. Fill each with about 1/2 teaspoon of preserves. Bake until golden brown, about 20-25 minutes. Immediately remove fromcookie sheets.
