01 - Preheat oven to 350°F. Grease and line a 9x5-inch loaf pan with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
03 - In a large bowl, beat butter and sugar until light and fluffy, about 2 to 3 minutes.
04 - Beat in eggs one at a time, mixing well after each addition.
05 - Stir in lemon zest, lemon juice, and vanilla extract.
06 - Add half the flour mixture and mix gently, then add the milk and continue mixing. Add the remaining flour mixture and stir until just combined. Avoid overmixing.
07 - Pour batter into prepared loaf pan and smooth the surface.
08 - Bake for 45 to 50 minutes, or until a toothpick inserted in the center comes out clean.
09 - Let the cake cool in the pan for 10 minutes, then transfer to a wire rack and cool completely.
10 - Whisk powdered sugar and lemon juice until smooth and pourable. Adjust consistency with additional lemon juice if needed.
11 - Once cooled, drizzle the lemon icing over the cake and allow it to set before slicing.