01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl; set aside.
03 - In a large bowl, beat softened butter and sugar until light and fluffy, about 2 to 3 minutes.
04 - Add eggs one at a time, mixing well after each. Stir in lemon zest and vanilla extract.
05 - Add flour mixture in three portions, alternating with lemon juice and milk, beginning and ending with flour; mix gently until just combined.
06 - Pour batter into prepared pan and smooth the surface evenly.
07 - Bake for 45 to 55 minutes until a toothpick inserted into the center comes out clean or with a few moist crumbs.
08 - Allow bread to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
09 - Whisk powdered sugar with lemon juice until smooth and pourable; drizzle over cooled loaf and let glaze set before slicing.