Place sugar with 2 tablespoons of cold water in a saucepan.
Place the pan over medium heat and let it boil.
Watch the saucepan until the water evaporates and the sugar becomes golden brown.
As soon as the sugar has reached the desired color, add the butter and stir vigorously with a whisk until butter is completely dissolved.
Separately, in a kettle or a saucepan, heat the cream.
Once the butter melts completely, pull the pan from the heat and add cream, stirring vigorously with a whisk. The composition will bubble and swell a lot at this stage.
Add the vanilla extract and salt and mix well. Also now add 1/2 teaspoon of lemon juice.
Pour the salted caramel sauce in a jar and let it cool at room temperature, then refrigerate.
Slightly warm up when serving the sauce.