Start by preparing the cookie:
In a bowl, beat your egg whites using an electric mixer.

Then add the powdered sugar and continue beating until you get a meringue-like consistency.

Using a spatula, gradually fold in the almond flour until you have a smooth mixture.

Preheat your oven to 350°F.

On a baking sheet lined with parchment paper, place your A4 sheet under the parchment paper (to easily trace your number or letter).

Using a piping bag, trace your number with the cookie mixture.

Repeat the previous 2 steps for the second cookie.

Bake for 10 minutes.

In a bowl, mix the cream, mascarpone, and Nutella with an electric whisk until the mixture doubles in volume and is smooth.

Fill your first layer of cookie with the Nutella cream using a piping bag, then cover it with the second cookie and fill it with the remaining cream.

Decorate with assorted Kinder chocolates.