Cream together the butter, sugar and vanilla extract. Add the eggs and mix well. Add the flour and knead to form a firm dough.
Shape the dough into balls (40 pieces). Leave to rest in the fridge for at least an hour.
Heat the waffle iron and grease it. I use baking spray. Place a ball of dough in the iron and close the iron. Bake for a few minutes until the waffle is golden brown.
Use a spatula to transfer the waffle to a wire rack. Leave to cool and crisp up. Continue until you have made all the waffles.
Tips
There are special irons for these waffles, but I used a waffle iron for thin waffles, which also works well for stroopwafels.
How to store
Keeps for at least 2 weeks in an airtight container outside the fridge.