Lemon Squares I
["1 1/2 c. sifted flour", "1/2 tsp. baking powder", "1/2 tsp. salt", "3 egg whites, beaten", "1 c. sifted powdered sugar", "1/2 c. chopped pecans", "1/2 c. butter", "1 c. sugar", "3 egg yolks", "1/3 c. lemon juice", "2 Tbsp. grated lemon rind"]
["Beat egg whites until soft mounds are formed.", "Add the powdered sugar gradually.", "Beat until stiff; set aside.", "Cream butter and sugar well.", "Add egg yolks, one at a time, beating well after each.", "Sift flour, baking powder and salt; add alternately with lemon juice, beginning and ending with dry ingredients.", "Add lemon rind and pecans.", "Gently fold in beaten egg whites and pour into greased and floured 13 x 9 x 2-inch pan.", "Bake at 400\u00b0 for 25 to 30 minutes.", "Frost while still warm; sprinkle with chopped pecans."]
["flour", "baking powder", "salt", "egg whites", "powdered sugar", "pecans", "butter", "sugar", "egg yolks", "lemon juice", "lemon rind"]