Begin by preparing a baking sheet with parchment paper.

Using a spoon, scoop out approximately 1-2 teaspoons of Nutella for smaller cookies or 1-2 tablespoons for larger cookies. Place the Nutella portions on the baking sheet, shaping them into rounds or ovals as much as possible. For larger cookies, you may need to use additional Nutella beyond the listed amount.

Place the baking sheet with Nutella in the freezer to allow the spread to firm up.

In a separate large bowl, whisk together the flour, baking soda, baking powder, and salt. Set this mixture aside.

Using a stand mixer or hand mixer, cream together the softened butter and 1 1/2 cups of granulated sugar on medium speed for about 3-5 minutes, or until the mixture is light and fluffy.

Lower the mixer speed to add the egg and vanilla extract. Mix thoroughly until well incorporated.

Remove the bowl from the mixer, and gently fold in the dry ingredients with a spatula. Stir until fully incorporated, ensuring the dough remains soft and slightly tacky.

Cover the dough with plastic wrap and refrigerate it for one hour.

Preheat your oven to 350°F (175°C) and line a large baking sheet with parchment paper. Add the remaining 1/2 cup of granulated sugar to a small bowl for later use.

Remove the chilled dough and frozen Nutella from the refrigerator and freezer. For smaller cookies, take about 1-2 teaspoons of dough and flatten it into a circle around 1-2 inches in diameter. For larger cookies, scoop out about 1-2 tablespoons of dough and flatten into a 2-3 inch circle. Form two flat dough pieces per cookie, placing a portion of frozen Nutella between them. Pinch the dough edges together and roll the ball in the sugar to coat the outside. Place each cookie ball on the prepared baking sheet, leaving about 2 inches between them. You may need to pause periodically to freeze the Nutella again to prevent it from melting during assembly.

Bake the smaller cookies for 10-12 minutes and the larger ones for 14-16 minutes. The cookies are done when the tops begin to crinkle and the bottoms are a light golden brown.

Allow the cookies to rest on the baking sheet for 5-10 minutes before transferring them to a wire rack to cool completely.

Serve and enjoy as desired.