Place the heavy cream in a chilled bowl.

Using a mixer, beat on medium speed until it begins to thicken then turn
it on high speed until it begins to thicken and become the consistency
of whipped cream.

Add in the sweetened condensed milk and vanilla and beat on high for 2 minutes.

Pour into a container to freeze.

Heat the lemon curd in a microwave safe dish for 15-20 second or just until it is easy to stir.

Add the curd to the cream mixture and swirl it in with a butter knife so that it goes all through the ice cream.

Add the shortbread pieces and gently fold them in.

Cover and freeze for 4-6 hours.