Preheat oven to 350°F (180°C). Grease and flour a 9x5-inch loaf pan.
In a bowl, whisk flour, baking powder, and salt. Beat sugar, eggs, vegetable oil, lemon juice, and zest until smooth and light.
Add dry ingredients to the wet in two batches, alternating with milk and vanilla. Stir gently until combined.
Pour the batter into the pan. Tap it to release air bubbles. Bake for 50–60 minutes or until a toothpick comes out clean.
Let the loaf cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
Whisk together confectioners' sugar, lemon juice, and zest until smooth. Drizzle the glaze over the cooled loaf and let it drip down the sides.