Preheat the oven to 350F then line a baking sheet with parchement paper and set it aside.
Cream the butter, granulated sugar, and powdered sugar together until smooth and creamy.
1/2 cup butter, 1/3 cup granulated sugar, 3 tbsp powdered sugar
Whisk in the egg, vanilla butter emulsion and mix until combined.
1 egg, 3 tsp vanilla butter emulsion
Mix in the flour, baking powder, cornstarch, salt until the flour mixture disappears. Don't over mix your dough. Then using a large cookie scooper scoop out 6 equally sized cookie dough balls, place them on the prepared baking sheet and gently flatten them to about 1 inch in thickness.
1 & 1/2 cup all purpose flour, 1 tbsp cornstarch, 1/4 tsp salt, 3/4 tsp baking powder
Bake the cookies in the oven for 11 minutes, then let them cool down on the baking sheet for 10-15 minutes before transferring to a cooling rack to cool down fully.
Top each cookie with 1 tablespoon worth of Nutella or more, sprinkle with sea salt and enjoy!
6 tbsp Nutella, Sea salt