Mix the sugar, cocoa, and salt in a bowl.

In a medium saucepan, melt the butter over medium heat. Add the chocolate and stir until melted.

Add cream and the sugar/cocoa mixture. Stir until creamy and smooth.

Pour into a square dish. Cover and refrigerate for several hours until chocolate is set.

Remove chocolate from the refrigerator.

Use a teaspoon to scoop out chocolate. 

Roll into bite-sized balls with a hazelnut at the center. They might be hard to roll at first, but as the chocolate warms to room temperature, it will become easier to work. If chocolate becomes too soft, return to the refrigerator for a few hours.

Roll balls in cocoa powder. Serve immediately or store in a covered container in the refrigerator.

*For a little extra crunch, use chocolate bars with nibs added or toss a small handful of chocolate nibs into the melting chocolate. 

If the truffle candy sticks to your hands too much while rolling, liberally dust your clean hands with cocoa powder then try again.