Roast the hazelnuts in a preheated oven at 180°C (350°F) for about 15 minutes, stirring halfway through.
Leave to cool, then rub with a cloth to remove the skin. You can buy them already peeled.
Reserve 120 g (4.2 oz) for making the praline and blend the rest with the sifted powdered sugar. Blend until smooth.
Add a tablespoon of oil to help with blending. Once the hazelnut paste is smooth, place in a bowl.
Place the caster sugar in a saucepan over medium heat to prepare a dry caramel. Let the sugar caramelize without stirring.
Gently swirl the pan. Remove from heat when caramel is golden. Be careful, it's better to remove it while it's still light rather than too dark, as it can taste bitter.
Add the 120 g (4.2 oz) of reserved hazelnuts and mix well to coat them with the caramel.
Pour the mixture onto a Silpat or your work surface. Leave to cool a little and crush coarsely to facilitate blending.
Blend until smooth. Place in a bowl.
Melt the chocolates in a double boiler.
Sift the powdered milk and cocoa over the hazelnut paste (duja).
Add the pinch of salt, oil, melted chocolate and hazelnut praline. Mix well.
Remix in food processor to homogenize and refine the mixture. Be careful not to heat the spread while blending.
If you mix it for too long, you risk either making the spread too thick or too runny.
Stop as soon as it has the desired texture. Pour into a jar and give the bowl to your son or daughter to clean up. These things are not to be wasted, as my beloved chef, Mr. Philippe Conticini, would say.
You can store it for two weeks at room temperature.
This easy recipe for homemade Nutella is very tasty and sure to please your kids.