Stir together 1 cup flour and ¼ cup powdered sugar. Cut in butter until the mixture clings together. Pat into an ungreased 8” x 8” glass baking pan. Bake at 350ºF for 10-12 minutes. In a mixer bowl, beat eggs; add granulated sugar and lemon juice. Beat until slightly thickened and smooth, 8-10 minutes. Stir together 2 Tbsp flour and baking powder; add to egg mixture. Blend until all is moistened. pour over crust. Bake at 350ºF for 20-25 minutes. Sift powdered sugar over top. Cool, then cut into bars.