Step #4 In a small bowl (or liquid measuring c), mix buttermilk with lemon zest & juice.
Step #5 In a medium bowl, whisk together flour, salt, baking powder, & baking soda.
Step #6 With an electric mixer, cream butter & sugar until light & fluffy.
Step #7 Add eggs, one at a time, beating until incorporated after each.
Step #8 With mixer on low, add flour mixture in three parts alternately with the buttermilk mixture in two, beginning & ending with flour; beat just until smooth (do not overmix).
Step #9 Divide batter evenly between pans; smooth tops.
Step #10 Bake until a toothpick inserted in centers comes out clean, 50 to 60 mins (tent with foil wrap if browning too quickly).
Step #11 Cool 15 mins in pan.
Step #12 Turn out cakes onto a rack; cool completely before glazing.
Step #13 Set rack with cakes over a baking sheet lined with waxed paper.
Step #14 GLAZE:.
Step #15 Place confectioners' sugar in a medium bowl or liquid measuring c; stir in the lemon juice (glaze should be thick, yet pourable).
Step #16 Add more sugar or lemon juice, as necessary, to achieve desired consistency.
Step #17 Pour glaze over cakes, letting it run down the sides; let dry, about 30 mins.