Preheat the oven to 350 degrees. Fill a sauce pan with 1 inch of water and boil over medium heat. Spread the hazelnuts on the baking sheet and bake in the oven for 8 minutes, watching carefully to make sure they don't burn.
Once the water boils, place a dry metal or glass bowl on top of the saucepan to trap the heat and be warmed by the steam. This creates a double-boiler effect that melts the chocolate without burning. Make sure the bowl fits snugly on top of the sauce pan or pot, and that the water does not touch the bottom of the bowl. Add the chocolate chips to the bowl and let them melt, stirring occasionally.
Remove hazelnuts from the oven, place on a kitchen towel to cool and rub gently to remove any skins that are flaking off. Place into food processor or blender and blend until they are a fine texture. Add nuts into the melted chocolate along with coconut oil. Stir well and fold in rice puffs. Press into a parchment paper-lined mold in the baking pan, and place into freezer for 10 minutes to firm up. Cut into bars and enjoy!