Partially defrost the frozen raspberries in a bowl and then use a fork to mash them up.
Add the zest of 1/2 lime and then the juice of the 1/2 lime to the bowl of raspberries.
Then add the can of sweetened condensed milk and combine.
In another bowl, pour the cream and using beaters, whip the cream until soft peaks form.
Carefully pour the raspberry mixture into the whipped cream and gently fold together.
Then pour the entire mixture into your tin or container, lightly cover with cling film and place into the freezer for 4-6 hours until frozen, or overnight.