Preheat your oven to 350°F (175°C).

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy, about 3 to 5 minutes.

Beat in the eggs, one at a time, then stir in the grated lemon zest and lemon juice.

In another bowl, combine the flour, baking powder, salt, and poppy seeds.

Gradually add the dry mixture to the wet mixture, alternating with the milk.

Pour the batter into a greased 9-inch round cake pan.

Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.

Let it cool in the pan for a few minutes before transferring it to a wire rack to cool completely.

Dust with powdered sugar if desired before serving.