Preheat your oven to 350°F (175°C). Grease a 9-inch springform pan.

In a mixing bowl, cream together the butter and sugar until light and fluffy.

Add the eggs and vanilla extract, mixing until smooth.

Gradually mix in the flour and baking powder until just combined.

In a saucepan, combine the poppy seeds, sugar, milk, and semolina. Cook over medium heat while stirring until thickened, about 5-7 minutes.

Remove the mixture from the heat and let it cool to room temperature.

Create the crumble by combining flour, sugar, and cold butter in a separate bowl. Mix until crumbly.

Spread half the cake batter smoothly across the bottom of the prepared pan.

Pour the cooled poppy seed filling over it, then top with the remaining batter.

Sprinkle the crumble mixture evenly on top.

Bake for 40-45 minutes until the top is golden brown and a toothpick comes out clean.