• Line an 8-inch (20 cm) loaf pan with parchment paper, allowing the paper to hang over the sides.

Make the raspberry ice cream layer:

• Add the raspberries and half of the lemon zest and juice to a food processor and process until as smooth as possible. Add 400g of the softened vanilla ice cream to the food processor and pulse until combined.
• Spoon the raspberry ice cream into the loaf tin. Use a spoon or spatula to smooth the surface (note 2). Dollop and spread half of the raspberry jam on top. Freeze for 1 hour or until set.

Make the vanilla ice cream layer:

• Scoop 200g of the softened vanilla ice cream into the loaf tin. Use a spoon or spatula to smooth the surface. Dollop and spread the remaining raspberry jam on top. Return the pan to the freezer for 1 hour or until set.

Make the blueberry ice cream layer:

• Add the blueberries and the remaining lemon zest and juice to a food processor and process until as smooth as possible. Add the remaining 400g of softened vanilla ice cream to the food processor and pulse until combined.
• Spoon the blueberry ice cream into the loaf tin. Use a spoon or spatula to smooth the surface. Set aside the tin in the freezer for 2 hours or until set.

To serve:

• Remove the ice cream from the tin by pulling on the baking paper. If it doesn't pop out, carefully run the tin under warm water then remove. Use a sharp knife to cut portions out of the cake. Top the cake with fresh berries and serve immediately. Store the leftovers in an airtight container in the freezer for up to 1 month.