Line a 9x5-inch loaf pan with plastic wrap. Place 1 cup of the chopped hazelnuts in the bottom of the pan. Set aside. Place remaining hazelnuts and Himalayan Pink Salt in food processor; cover. Process until mixture resembles fine crumbs. Set aside.
Place cream and chocolate in a double boiler; whisk until chocolate is melted and smooth. Remove from heat. Stir in ground hazelnut mixture. Allow to cool completely at room temperature.
For the meringue, combine sugar and water in a small saucepan. Cook over medium heat until temperature reaches 250°F.
Meanwhile, place egg whites in bowl of electric mixer fitted with whisk attachment. Beat until soft peaks form. Stir in vanilla extract.
Gradually add hot syrup mixture to egg whites, stirring constantly. Beat until meringue is fluffy and stiff peaks form, about 6 minutes.
Mix cooled chocolate mixture with a wire whisk until soft peaks form. Gently stir chocolate mixture into meringue. Transfer mixture to prepared pan and freeze at least 4 hours or until firm. Let stand at room temperature 15 minutes before serving. Garnish with whipped cream and sprinkle with additional Himalayan Pink Salt, if desired.
Test Kitchen Tip: Don’t have a double boiler? —Make your own. Mix cream and chocolates in a medium heatproof bowl. Fill a small saucepan about 1/4 of the way with water and bring to a simmer. Place bowl with chocolate mixture on top of the saucepan and continue to cook as directed.