1.Take out a 10-inch tube pan with a removable bottom and DO NOT GREASE THE PAN! Sift together flour, sugar, baking powder, and salt into a large bowl. Sift again and whisk well, set aside.
2.Divide the eggs, placing the whites in the bowl of an electric mixer and the yolks in a medium bowl. Add water, 1/4 cup lemon juice, oil, lemon zest and vanilla extract to the medium bowl with eggs yolks and whisk until well combined.
3.Add the liquid ingredients to the dry ingredients and whisk until blended. Preheat oven to 325 degrees.
4.Beat egg whites with cream of tartar until soft peaks form. When you pull the beaters out of the egg whites, the peaks will fall over. Make sure not to beat until it forms stiff peaks.
5.Using a spatula, softly fold ⅓ of the egg whites into the lemon cake batter. Repeat with the remaining egg whites until fairly well blended. There will still be some white streaks showing. Spoon the batter into the tube pan. When done, cut through the batter with a knife to eliminate any air pockets that may have formed.
6.Bake for 60 minutes. It’s done when the top springs back when lightly touched. Remove from oven and immediately invert pan. If your pan does not have feet, invert it over a long-necked bottle. Let it cool for 1 hour.
7.Meanwhile mix powdered sugar, 1 tablespoon lemon juice and milk in a small bowl.
8.When the cake is cool, run a knife around the outside edges, the bottom, as well as the center tube to loosen. Turn cake out and invert onto a serving plate. Drizzle the glaze over the top of the cake and allow the excess to drip down.