Start by cutting all the oranges in half and squeeze out all their juice, then transfer all this juice to a bowl.
Pour in the condensed milk and mix very well for 10 minutes.
Finely chop the milk chocolate bar into shavings and set aside.
Now, in another bowl, add the heavy cream and beat with an electric mixer until stiff peaks form. Pour in the orange cream and beat again.
Also add all the chocolate shavings and mix again with a spatula.
Add the orange zest and mix once again.
Transfer all this mixture to a dish and take it to the freezer, let it chill for at least 6 hours.
Serve.