Preheat oven to 325°F (160°C).

Grease and flour a 9-inch springform pan.

In a medium bowl, cream together the butter and sugar using a mixer until light and fluffy.

Add the eggs one at a time, mixing well after each addition.

Stir in the chocolate syrup and vanilla extract.

In a separate bowl, whisk together the flour and baking powder.

Gradually add the dry ingredients to the wet ingredients, mixing by hand until just combined.

Pour the batter into the prepared springform pan.

Bake for 60-75 minutes, or until a wooden skewer inserted into the center comes out clean.

Let the cake cool in the pan for 10-15 minutes before releasing it from the springform pan.

Allow the cake to cool completely before slicing and serving.