For the manjar blanco, mix the condensed and evaporated milk in a large pan. It's better to use a large pan than a deep pot because you increase the surface area with direct heat, making it cook quicker. Stir constantly scraping the bottom and the edges to prevent burning. The process will take around 30-35min, until you can see a large portion of the bottom of the pan if you move the mix around.
Let it cool down to room temperature before moving on to the mousse.
For the praline, first we need to make a direct caramel. Start by spreading a bit of sugar on the bottom of the pan, making a thin layer. Melt it on low-medium heat and pour a thin layer of sugar where it melts. Repeat until you've used up the recipe amount. Lower the temperature if you think it's caramelizing faster than you can control. Let it caramelize to a nice golden colour. Don't use any utensil to move the caramel around or crystals will form. If you need to move it around, move around the pan using the handle.
Once it's all melted and golden, add the hazelnuts and mix quickly. Then the mix goes onto a silpat mat or baking paper to cool down completely - please be careful, it's extremely hot! Once they have cooled down, separate the individual hazelnuts, chop them, or both. Keep them in an airtight container as caramel melts with humidity.
When it's cold enough, separate the hazelnuts individually. You can also chop them if you prefer or even do both like I did.
For the mousse, whip the whipping cream (which must be cold) until you get a nice fluffy texture. Don't over whip it or you'll get a thick butter texture.
Take out the cream from the bowl and whip the manjar blanco until no lumps remain. Then add about a third of the whipped cream and mix with the machine also.
Fold in the rest of the cream using a spatula, being careful not to knock out the air from the mix.
I put the mix in piping bags and served on individual containers. However, you can always use a large one and serve from there.
Put the mousse in the fridge at least 6 hours if in individual containers and 8 hours if in a large container to achieve the perfect texture.
Put the hazelnut praline and chocolate chips just before serving so that they don't melt (the praline) or sweat (the chocolate) in the fridge.