Preheat oven to 350° F. Grease a 9×13-inch baking pan, then set aside.
- Beat butter and sugar together in a mixing bowl.
- Add well-beaten eggs and mix together with the butter and sugar.
- Add the lemon zest, milk, flour, salt, and baking powder to the mixing bowl and mix everything together well.
- Pour batter into baking pan. Bake at 350° F. for 40 minutes or until cake tests done. Cool completely before adding glaze.
- Add lemon juice into a bowl and slowly whisk in powdered sugar, half a cup at a time until thick enough to spread over cake.
- Pour over the top of cooled cake and use a knife to spread evenly over cake, letting the icing drip over sides of cake.