Line a rectangular baking dish with parchment paper.
- Combine crushed biscuits and melted butter, then press firmly into the base of the dish. Freeze for 15 minutes.
- Whip heavy cream until soft peaks form in a large bowl.
- Fold in sweetened condensed milk and softened vanilla ice cream until well combined.
- Gently stir in most of the crushed honeycomb candy, reserving some for the topping.
- Pour the ice cream mixture over the chilled biscuit base and smooth the top.
- Sprinkle the reserved honeycomb over the top of the mixture.
- Freeze for at least 6 hours or overnight until firm.
- Slice into squares or rectangles using a hot knife and serve immediately.