Preheat the oven to 350°F (175°C) and grease a cake pan.
In a large bowl, cream together the butter and sugar until light and fluffy.
Add the Biscoff cookie butter and mix until well combined.
Beat in the eggs one at a time, then stir in the milk.
In another bowl, whisk together the flour, baking powder, baking soda, and salt.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Pour the batter into the prepared cake pan and smooth the top.
Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.
Let the cake cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
