Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
In a medium bowl, mix together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla, lemon juice, and poppy seeds.
Add the flour mixture alternately with the buttermilk. Beat until just combined.
Pour the batter into the prepared pan. Bake for 30 minutes in the preheated oven, or until a toothpick inserted into the center of the cake comes out clean.
To make the glaze, mix together the confectioners' sugar and lemon juice until smooth. Drizzle over the cooled cake.
Interesting Facts
Poppy seeds are a type of edible seed from the poppy plant.
Lemon poppy seed cake is a classic flavor combination that originated in Germany.
This cake is perfect for any occasion, from birthdays to baby showers.