Step 1

Melt butter and set aside to cool down.

Step 2

In a medium bowl, combine flour, baking soda, vanilla and salt. Set aside.

Step 3

In a large bowl, combine both sugars with the cooled, melted butter, and stir well until no lumps remain. Add in the egg, egg yolk and milk well.

Step 4

Pour the dry ingredients into the liquid ingredients, mixing until everything is incorporated. Add the Daim pieces and mix to combine.

Step 5

Cover the bowl with clingfilm, place in the refrigerator and let chill for about 2 hours.

Step 6

Preheat the oven to 375°F (190°C) and line a baking tray with parchment paper.

Step 7

Once the dough has chilled, remove it from the refrigerator and let sit at room temperature for about 10 minutes before using it.

Step 8

Form the dough into balls and place onto the baking tray, leaving enough space between each.

Step 9

Bake for about 8-10 minutes or until just golden while still looking slightly under-cooked inside (it’s normal). Remove from the oven and sprinkle some additional sea salt on top. Let cool for one minute onto the baking tray, then transfer to a cooling rack and let cool completely.