1½ cups (300 gr) sugar
4 tablespoons (60 gr) salted butter
scant ½ teaspoon sea salt
1 cups (250 ml) heavy cream
5 large egg yolks
¾ teaspoon vanilla extract
To make the ice cream, make an ice bath by filling a large bowl about a third full with ice cubes and adding a cup or so of water so they're floating. Nest a smaller metal bowl (at least 2 quarts/liters) over the ice, pour 1 cup (250 ml) of the milk into the inner bowl, and rest a mesh strainer on top of it.
Spread 1½ cups (300 gr) sugar in the saucepan in an even layer. Cook over moderate heat, until caramelized, using the same method described in Step #2.
Once caramelized, remove from heat and stir in the butter and salt, until butter is melted, then gradually whisk in the cream, stirring as you go.
The caramel may harden and seize, but return it to the heat and continue to stir over low heat until any hard caramel is melted. Stir in 1 cup (250 ml) of the milk.
Whisk the yolks in a small bowl and gradually pour some of the warm caramel mixture over the yolks, stirring constantly. Scrape the warmed yolks back into the saucepan and cook the custard using a heatproof utensil, stirring constantly (scraping the bottom as you stir) until the mixture thickens. If using an instant-read thermometer, it should read 160-170 F (71-77 C).
Pour the custard through the strainer into the milk set over the ice bath, add the vanilla, then stir frequently until the mixture is cooled down. Refrigerate at least 8 hours or until thoroughly chilled.
Freeze the mixture in your ice cream maker according to the manufacturer's instructions.
*There is an additional caramel praline that can be added, but I did not enjoy it.