Brownies are the perfect easy to make dessert any time of the year and a great food item to plan to take to your next pot luck or family picnic.
Preheat the oven to 375F.
Line an 8x8-inch baking dish with aluminum foil that goes up the sides and grease the foil. This will make for easier removal from the pan after the brownies are baked.
Stir the flour, cocoa, cinnamon, baking powder and salt together in a mixing bowl until well combined.
Melt the butter in a small saucepan over medium heat; remove pan from heat and stir in chocolate until melted.
In a large mixing bowl, beat together the melted chocolate and sugar using an electric mixer on high speed. Beat for 2 minutes until well combined, reduce the speed to medium and beat in the Nutella, eggs and vanilla.
Mix until well combined.
Add the flour mixture a little at a time and mix in with low speed until just combined.
Transfer the batter into the prepared baking dish.
Sprinkle the chocolate pieces and hazelnuts on top.
Place into the preheated oven and bake for 20-25 minutes or until a toothpick inserted in the middle comes out clean.
Remove from the oven to a cooling rack.
Let cool completely then lift the brownies out of the pan with the aluminum foil.
Chill for easier cutting.