Preheat the oven to 350° Fahrenheit. Line a loaf pan with parchment paper and set aside.
Cream butter and sugar in a large bowl with an electric mixer on high until pale and creamy. About 3 minutes. Add the eggs, lemon juice, and vanilla extract and continue to beat on a medium-high.
Add flour, baking powder, poppy seeds, lemon zest, and salt. Beat on a low speed until well combined. Reduce speed to low speed and add the milk. Continue to beat until the batter is smooth.
Pour the batter into the prepared loaf pan and bake for 55-60 minutes. Use a wooden toothpick to check for doneness. Allow the bread to cool in the loaf pan for 10-15 minutes before transferring it to a wire cooling rack.
To make the lemon glaze, add the powdered sugar and 2 tablespoons of lemon juice to a mixing bowl. Whisk until smooth and well combined, adding more lemon juice if needed until a drizzling consistency is reached. Drizzle over the cooled cake.