Preheat oven 350 F
Mix flour, baking soda, salt and poppy seeds
Beat butter and sugar until fluffy then beat in egg and lemon peel
Gradually beat in flour mixture
Drop dough by generous teaspoon on ungreased baking sheets and bake for 11-12 mins
Cool on rack completely before glazing
Mix icing sugar and lemon juice, pour into piping bag or ziplock bag, and glaze cooled cookies
Let icing harden before storing