1. Make the caramel by combining the sugar and 80ml water in a saucepan, stir over medium-high heat until sugar dissolves, bring to the boil and cook until a medium dark colour.
  2. Remove from heat and carefully add the cream. Whisk until smooth, add the peanut butter, sea salt and peanut oil. Cool.
  3. Allow the ice cream to soften slightly by standing at room temperature for 15 minutes.
  4. Transfer ice cream to a large metal bowl and with a heavy spoon, stir in the caramel through in a ripple effect.
  5. Return the ice cream to the ice cream container and freeze until firm.