1. Preheat the oven to 325F. Grease a 9x5 loaf pan and sprinkle lightly with flour. In a medium bowl, whisk together the eggs, vanilla and lemon zest.

2. In a separate large bowl, beat the butter on medum speed with an electric mixer. Add the sugar 1/3 cup at a time, adding the salt in with the last batch. Mix until the butter starts to become fluffy, 4-6 minutes. Add the egg mixture slowly, mixing until the batter is light and pale yellow, another 3 minutes.

3. Sift the flour through a wire strainer into the batter 1 cup at time, mixing on low speed to combine. Use a rubber spatula to scrape down the sides.

4. Pour the batter into the pan, and shake gently to make sure there are no air pockets. Bake until a toothpick comes out clean, about 1 hour.