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 - In a large bowl, beat butter and sugar together until light and fluffy, about 2 to 3 minutes.
04 - Beat in eggs one at a time, mixing well after each addition, then stir in lemon zest and vanilla extract.
05 - In a small bowl, mix milk and fresh lemon juice.
06 - Add the flour mixture to the wet ingredients in three additions, alternating with the milk-lemon juice mixture, beginning and ending with the flour mixture. Mix until just combined to avoid overmixing.
07 - Pour the batter into the prepared loaf pan and smooth the surface evenly.
08 - Bake for 45 to 55 minutes, until a toothpick inserted in the center comes out clean.
09 - Let the loaf cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
10 - Whisk powdered sugar with 2 tablespoons lemon juice until smooth; add more lemon juice if needed to achieve a pourable consistency.
11 - Drizzle the glaze over the cooled loaf and allow it to set before slicing.