Prepare shortbread: combine 1-1/4 cups flour, 1/3 cup granulated sugar and 1/2 cup butter. Blend to fine crumbs. Press firmly into bottom of greased 8 inch square pan. Bake at 350 degrees about 25 minutes or until lightly browned. Mix raisins & jam. Spread over shortbread. Beat eggs with brown sugar, flour, baking powder and salt. Stir in walnuts, orange peel and vanilla. Pour mixture over top. Return pan to oven. Bake 35 to 40 minutes until top is browned and springs back when punched.. Cool in pan. Sift with powdered sugar. Cut into 24 bars.