01 - Preheat oven to 350°F. Generously grease and flour a 10–12-cup Bundt pan, ensuring all crevices are coated.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, salt, and poppy seeds. Set aside.
03 - In a large bowl or stand mixer, beat butter and sugar on medium speed until light and fluffy, about 3 to 4 minutes.
04 - Add eggs one at a time, beating well after each addition. Stir in lemon zest and vanilla extract.
05 - Combine fresh lemon juice and milk in a measuring cup.
06 - With mixer on low speed, alternate adding the flour mixture and lemon juice-milk mixture to the batter, beginning and ending with flour. Mix until just combined, avoiding overmixing.
07 - Pour batter evenly into the prepared Bundt pan and smooth the top with a spatula.
08 - Bake for 45 to 55 minutes or until a skewer inserted in the center comes out clean.
09 - Let the cake cool in the pan for 15 minutes, then invert onto a wire rack and cool completely.
10 - Whisk powdered sugar, fresh lemon juice, and lemon zest until smooth and pourable.
11 - Drizzle glaze over the cooled cake and let it set before slicing.