In a large mixing bowl, add the whipping cream and instant coffee. With a whisk or electric beater, whip the whipping cream until it reaches soft peaks and the coffee has dissolved.
Slowly drizzle the condensed milk into the whipped cream while gently folding it in with a rubber spatula at the same time. Only fold until just combined. The whipped cream should still hold soft peaks.
Add in the chopped dark chocolate and fold just a couple of times to combine.
Pour the mixture into a loaf tin and cover with plastic wrap. Freeze for at least 4 hours or preferably overnight.
When serving, run an ice cream scoop under hot water before scooping.