Make a thin layer of sugar on a pan and put it on medium heat. As some spots start to melt cover them with a thin layer of sugar. Continue until you have used up all the sugar in the recipe.
Let it become a nice pale gold colour and don't use any utensil to mix at this point, only move around the sugar by tilting the pan. Voilá! You've made direct caramel.
Once golden, add the cream and salt and stir vigorously. Be really careful because it's really hot and it will bubble up.
Remove the pan from the heat, add the butter and stir. Let it cool down completely.
If it's too thick, you can adjust the texture by warming it up and adding a bit of boiling water.