Preheat the oven to 350° F (180°C). Line you baking sheet with parchment paper or a silicone baking mat. Set aside.
In the bowl of a stand mixer or with an electric hand mixer, cream together the butter and sugar until well combined.
3 tbsp butter, 4 tbsp granulated sugar
Scrape the sides of the bowl and add in the egg yolk, corn syrup and vanilla. Mix until combined.
1 egg yolk, 1/2 tbsp corn syrup, 1/2 tsp vanilla extract
Add the flour, baking soda and salt, mix until the dough forms.
2/3 cup + 2 tbsp all-purpose flour, 1/8 tsp baking soda, 1/8 tsp salt
Divide the dough into 6 equal sized portions and roll into balls.
Bake at 350°F (180°C) for 7-9 minutes or until the center of the cookies no longer look wet and glossy.
Allow the cookies to cool on the pan.
Store in an airtight container for up to 3 days.