In a medium bowl, whisk together the sweetened condensed milk, olive oil and salt until well combined.
In a separate larger bowl (or in the bowl of a stand mixer), whisk the heavy cream by hand or with a hand or stand mixer until stiff peaks form.
Add a dollop of the whipped cream to the smaller bowl with the condensed milk and stir vigorously to help loosen the condensed milk mixture.
Add the lightened condensed milk mixture to the whipped cream and, using a rubber spatula or large metal spoon, gently combine the two components by dragging the utensil under and over the mixture, scraping the sides and bottom of the bowl as you go.
Transfer to an airtight container and freeze until firm, at least 3 hours or overnight.
To a small microwave-safe bowl, add the sweetened condensed milk, chocolate and salt. Microwave on high in 30-second increments until the chocolate is completely melted, 30 to 60 seconds total.
Add the olive oil and stir vigorously until smooth.
To serve, let the ice cream sit at room temperature to thaw for at least 10 minutes before scooping, then top with the hot fudge sauce.
