Whip the heavy cream until stiff peaks form.
In a separate bowl, whisk together mascarpone, sweetened condensed milk, and vanilla extract until smooth.
Gently fold the whipped cream into the mascarpone mixture.
Crush the ladyfingers and mix them with the espresso or coffee.
Layer the ladyfinger mixture and the mascarpone cream in a freezer-safe container.
Freeze for at least 6 hours, or until firm.
Melt the dark chocolate with coconut oil.
Dip the ice cream into the melted chocolate to coat.
Sprinkle with cocoa powder before serving.
