Grind hazelnuts and pecans into the powder. Be careful not to over-grind as they will release oil very quickly.
Take the ground nuts into a thick-bottomed or non-stick pan and dry roast on medium heat. Roast the ground nuts, stirring continuously, for about 3-4 minutes until aromatic.
Now add milk, sugar, ghee, and salt into the ground nuts and stir well.
Bring this mixture to a boil on medium heat, stirring continuously.
Cook the mixture for 15-20 minutes, stirring constantly, or until it reduces into a thick mass. Depending on the heat, it may also take longer to reduce.
When the mixture is reduced and becomes a thick mass, it will start pulling away from the sides and bottom of the pan.
Now reduce the heat to low and stir the mixture for 5-7 minutes longer or until it becomes a solid, fudge-like mass that can easily move around the pan. It will also become shiny.
Turn off the heat and transfer the mixture into a greased plate or bowl. Allow the mixture to cool down to room temperature.
Scoop the mixture with a spoon, roll it to balls, and coat each ball with chopped nuts, if you prefer.