01 - Preheat oven to 350°F. Grease and line a 9x5-inch loaf pan with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl; set aside.
03 - Using an electric mixer or whisk, cream butter and sugar together until light and fluffy.
04 - Beat in eggs one at a time, mixing thoroughly after each addition.
05 - Mix in lemon zest, lemon juice, and vanilla extract until evenly combined.
06 - Alternate adding the flour mixture and milk to the wet ingredients, beginning and ending with flour; mix gently until just combined to avoid overmixing.
07 - Pour batter into the prepared loaf pan and smooth the surface evenly.
08 - Bake for 45 to 55 minutes or until a toothpick inserted in the center comes out clean.
09 - Allow the loaf to cool in the pan for 10 minutes, then remove to a cooling rack to cool completely.
10 - Whisk powdered sugar with lemon juice until smooth and pourable; drizzle evenly over the cooled loaf.
11 - Let the glaze set before slicing and serving.