• Preheat oven to 350°F. Lightly spray a 9×13-in. baking dish with cooking spray.

For the brownie layer:

• In a mixing bowl, combine the flour, sugar, cocoa,baking powder and salt.
• In another bowl, combine the oil, eggs and vanilla. Add the wet ingredients to the dry ingredients. Mix just until combined – Do NOT overmix. Spread into the prepared baking dish.
• Bake for 20-25 minutes or until a toothpick inserted near the center tests clean. Cool on a wire rack.

For the peanut butter fudge layer:

• In a medium saucepan, bring the milk and sugar to a boil. Boil for 4 minutes. Add the peanut butter and marshmallow creme and mix well. Quickly pour the mixture into the pan over the cooked brownie layer.
• Refrigerate for one hour.

For the chocolate ganache layer:

• Heat whipping cream in a small saucepan until hot but not boiling. Remove from the heat. Stir in chocolate until melted. Let stand for about 5 minutes. (The ganache is ready to use when the mixture mounds slightly when dropped from a spoon. It will become thicker as it cools.)
• Pour the ganache over the fudge layer and tilt the pan so the ganache flows evenly over the top, covering it completely.
• Allow to set completely before cutting into bars.