In a medium bowl, whisk together the heavy cream, whole milk, and granulated sugar until the sugar is completely dissolved. This will form the base of your ice cream.
Stir in the cooled espresso or strong coffee, vanilla extract, and sea salt until well combined.
Pour the mixture into an ice cream maker and churn according to the manufacturer's instructions, typically around 20-25 minutes, or until it reaches a soft-serve consistency.
Once churning is complete, swirl in the caramel sauce gently, creating a marbled effect without fully blending it in.
Transfer the ice cream to an airtight container, smoothing the top. Drizzle additional caramel sauce on top if desired.
Freeze for at least 4 hours, or until firm, before serving.
Notes
Serve scoops in chilled bowls and drizzle with extra caramel sauce. Add a sprinkle of espresso beans or chocolate shavings for added flair.