Preheat the oven to 350°F. Line a 9x13 baking pan with parchment paper leaving an overhang to help lift the brownies out of the pan.

Add the melted butter and unsweetened cocoa powder to a medium size mixing bowl, and whisk until completely combined.

Next whisk in the flour,granulated sugar and salt. The mixture will be crumbly.

Add in the eggs and vanilla extract. Use a handheld mixer on low speed to mix just until smooth. Bake for 23 to 25 minutes until a toothpick inserted comes out with a few moist crumbs.

Lower the mixer speed to low and add the sifted powdered sugar 1 cup at a time until smooth and creamy. (The mixture will be thick)

Add the dark chocolate chips to a heat safe small bowl. In a separate microwave safe bowl heat the heavy cream for 50 to 60 seconds, or until the cream begins to bubble.

Carefully pour the heated cream over the chips, and allow the chips and cream to sit for 1 to 2 minutes before stirring until smooth.

Immediately after removing the brownies from the oven, drop spoonfuls of the peanut butter filling over the top of the hot brownies. Use a spoon or an offset spatula to carefully spread the peanut butter filling.

Next spread the ganache over the peanut butter filling layer and chill in the refrigerator for about 2 hours, or until the ganache is set.

Use the parchment paper overhang to lift the chilled brownies out of the pan and place on a large cutting board.

Use a knife to slice the brownies into 12 even pieces before serving.