Preheat your oven to 350°F (175°C) and grease an 8x8-inch baking pan with cooking spray. Melt together unsalted butter and bittersweet chocolate in a double boiler until smooth. Stir in sugar, then add eggs one at a time, mixing well after each addition. Blend in flour, vanilla extract, and kosher salt until combined, pour batter into prepared pan. Bake for 20-25 minutes or until a toothpick inserted comes out mostly clean.

Dissolve gelatin in 1/4 cup of heavy cream over low heat. In a mixing bowl, whip remaining 1 1/4 cups of heavy cream until soft peaks form. Gradually fold in dissolved gelatin mixture, dark chocolate chips, and confectioners' sugar until well incorporated.

Once brownie base has cooled, spread chocolate filling evenly over top, smoothing surface with a spatula, and allow to set slightly while preparing topping.

Whip heavy cream with confectioners' sugar and vanilla extract until stiff peaks form. Spread whipped cream over chocolate filling for a lovely presentation.

Cover brownies tightly and refrigerate for approximately 4 hours or until filling and topping are firm. Chilling helps flavors meld and makes cutting easier.

Remove brownies from refrigerator, cut into squares with a sharp knife, and garnish with chocolate shavings or curls if desired. Enjoy!