Pam's Easy Blueberry Shortbread

Cream butter and sugar. Add eggs singly and beat until light and fluffy. Add flour and lemon rind. Put 1/2 dough in well-greased 9x13 inch pan and cover with pie filling. Drop remaining dough over top. Bake at 325 degrees for 45 minutes or until golden brown. Cool, top with icing. Icing: In a bowl, combine the confectioners' sugar, water and lemon juice; stir until combined and smooth (mixture will be thick). With a fork or small spatula, drizzle on top of cooled shortbread.