- Pre-heat oven to 400°.
- Grease a pie plate with butter or cooking spray.
- Beat 200g butter in a mixing bowl.***
- Add i beaten egg and Koopmans Butter cake.
- Knead until dough forms a ball.
- Place in the pie plate and flatten.
- Brush the top of the dough with egg white, if desired.
- Draw short lines in the dough with a fork to create a diamond pattern.
- Bake 22-27 minutes, until golden brown.
- Allow to cool for an hour before removing from pan.
***Cold butter can be difficult to mix. Try using a cheese grater to grate the butter.