01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line it with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl. Set aside.
03 - Using a mixer, beat softened butter and granulated sugar until light and fluffy, about 2 to 3 minutes.
04 - Mix in eggs one at a time, then stir in lemon zest and vanilla extract until incorporated.
05 - Add flour mixture in three parts, alternating with lemon juice and milk, beginning and ending with flour. Stir gently until just combined.
06 - Pour batter into prepared loaf pan and smooth the surface evenly.
07 - Bake for 45 to 55 minutes, or until a toothpick inserted in the center comes out clean or with few moist crumbs.
08 - Let the loaf 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 evenly over the cooled loaf and allow glaze to set before slicing.