Preparation

1. The day before, bring the milk, cream, halved vanilla pods and half the sugar to the boil in a saucepan. Leave to infuse off the heat.

2. Prepare the caramel:
   
   Melt the butter, vergeoise sugar and condensed milk in an uncovered saucepan over medium heat.From the boil, cook for 5 to 8 minutes without stirring. Remove from heat.Add the baking soda and fleur de sel. Leave to foam, then cool.

3. Whisk the egg yolks with the remaining sugar until the mixture whitens. Pour the milk over the eggs. Pour back into a saucepan and return to the heat. Cook, stirring constantly, until the cream "coats" a wooden spoon. Immediately pour into a cold bowl to stop the cooking. Stir in the caramel and refrigerate overnight.

4. The same day, set the mixture in an ice-cream maker according to the instructions. Once set, store in an airtight container in the freezer.

5. For an even more delicious and crunchy dessert, sprinkle a little Fleur de sel just before serving. In this case, remember to reduce the amount of salt in the preparation.