- Preheat oven to 350°F.
- Grease two 8½ x 4¼ x 2½ inch loaf pans.
- Cream butter and 2 cups of granulated sugar in the bowl of an electric mixer fitted with the paddle attachment, for about 5 minutes, or until light and fluffy.
- With the mixer on med.
- Speed, add the eggs, one at a time, and the lemon zest.
- Sift together flour, baking powder, baking soda and salt in a bowl.
- In another bowl, combine ¼ cup lemon juice, the buttermilk, and vanilla extract.
- Add the flour and buttermilk mixtures alternately to the batter, beginning and ending with the flour.
- Divide the batter evenly between the pans, smooth the tops, and bake for 45 minutes to 1 hour, until a cake tester comes out clean.
- Combine ½ cup granulated sugar with ½ cup lemon juice in a small saucepan and cook over low heat until sugar dissolves.
- When the cakes are done, let them cool for 10 minutes, then invert them onto a rack set over a tray, and spoon the lemon syrup over the cakes.
- Allow the cakes to cool completely.
- For the glaze, combine the confectioners' sugar and lemon juice in a bowl, mixing with a wire whisk until smooth.
- Pour over the top of the cakes and allow the glaze to drizzle down the sides.