I'm on my third round of this dessert tonight, and it's unbelievably tasty

Ingredients
3/4 cup all-purpose flour
1/4 cup unsweetened cocoa powder
1 teaspoon baking powder
1/4 teaspoon salt
4 large eggs
3/4 cup granulated sugar
1 teaspoon vanilla extract
1/2 cup hot chocolate cocoa mix
1 cup marshmallow fluff
1/2 cup heavy cream
Powdered sugar for dusting
Directions
Preheat your oven to 350°F (175°C). Line a 10x15 inch jelly roll pan with parchment paper and lightly grease it.
In a medium bowl, whisk together the flour, cocoa powder, baking powder, and salt.
In a large bowl, beat the eggs and sugar with an electric mixer on high speed until thick and pale, about 5 minutes. Stir in the vanilla extract.
Gently fold the dry ingredients into the egg mixture until just combined. Be careful not to overmix.