How to Make It
reheat oven to 350°F. Grease a 9- x 5-inch loaf pan with butter, and dust with flour, knocking the excess out of the pan. Beat eggs, flour, sugar, oil, sour cream, vanilla, lemon zest, baking soda, and 1/2 teaspoon of the salt with a hand mixer on medium-low speed until combined and smooth, about 2 minutes. Fold in blueberries. Pour into prepared loaf pan; smooth top. Bake in preheated oven until a wooden pick inserted in center comes out clean, about 1 hour, 15 minutes. Let cool in pan 20 minutes. Carefully remove cake from pan; transfer to a wire rack, and let cool completely, about 2 hours.
Whisk together powdered sugar, milk, lemon juice, and remaining 1/4 teaspoon salt in a bowl. Pour evenly over cooled cake. Garnish with additional lemon zest.