Golden Raisin Caramel:
- In a medium pot on medium heat, bring water and raisins to a light simmer. Reduce heat and cook 30 minutes. Strain the liquid into another container and set aside. Discard raisins (or use for another project).
- In a heavy-bottomed pan, cook sugar on high, stirring occasionally until golden-amber in color. Working quickly but carefully, whisk raisin water into sugar (the mixture will steam and foam). Set aside.
Ice Cream Base:
- Place milk and caramelized onions in a blender on high until it is a fine puree.
- Place egg yolks into a bowl and set aside.
- Heat onion milk, sugar and condensed milk in a pot on medium heat and stir occasionally until it comes to a light boil.
- Slowly whisk a third of the hot milk mixture into egg yolks, then add to the pot. Whisk constantly until mixture reaches 160°F.
- Remove from heat and pour into the cool milk to stop the cooking process.
- Strain and set aside to cool completely.
Churn ice cream base as per the instructions on your ice cream maker. Serve with raisin caramel and top with optional sea salt.