In a large mixing bowl, combine the melted butter and granulated sugar. Mix until well combined.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

In a separate bowl, whisk together the flour, cocoa powder, salt, and baking powder. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan and pour the brownie batter into the pan, spreading it evenly.

Bake in the preheated oven for 25-30 minutes or until a toothpick inserted in the center comes out with a few moist crumbs. Allow the brownies to cool completely in the pan.

While the brownies are cooling, whip the heavy cream with the powdered sugar and vanilla extract until stiff peaks form.

Once the brownies are cool, cut them into squares and layer them in a serving dish with whipped cream and chocolate chips, repeating the layers until all ingredients are used.

Cover the dish with plastic wrap and refrigerate for at least 4 hours or overnight to allow the flavors to meld.