Raspberry Ice Cream Sandwich

To make the semifreddo, blend the raspberries to a purée. Sieve the purée to remove the seeds and set to one side. Lightly oil a shallow tray (about 4cm) and line smoothly with a double layer of cling film.

Pour the egg whites into the bowl of a mixer with a whisk attachment. Put 80g of the sugar into a small saucepan along with 50ml of water. Place over a high heat. When the syrup reaches 110°C, turn the mixer to medium speed to start whisking the egg whites. When the syrup reaches 120°C, turn off the heat and turn up the mixer. Carefully pour the hot syrup onto the egg whites in a steady stream. Once all the syrup has been added, reduce to a medium speed and carry on whisking until the meringue base has cooled completely.

Meanwhile, combine the egg yolks and remaining sugar in a metal bowl set over a saucepan of
simmering water (bain-marie) to make a sabayon. Whisk the yolks and sugar over a gentle heat until they are light and pale; when you lift the whisk out, it should leave a ribbon trail that holds on the surface of the mixture before melting back in. Remove from the heat and leave to cool slightly.

Whisk the cream until it just holds soft peaks. Add the reserved berry purée and sabayon to the cream and gently fold through until just combined. Add the whisked meringue in two stages. Fold gently but firmly to ensure you maintain all of the volume you have worked hard to create but also to make sure you don’t have any pockets of meringue or cream.
Pour the semifreddo into the prepared tray, give it a gentle tap to make sure there are no air pockets, then freeze overnight. 

To make the cookies, toast the ground and blanched hazelnuts in the oven at 180°C for 10–15 minutes until deeply golden with an intense aroma. Leave to cool. Mix the butter, salt and sugars together until just combined. Add the vanilla pods to the butter and sugar along with the egg and mix well. Roughly chop the cooled nuts so you have a mix of large and small chunks. Sift together the flour, bicarbonate of soda and baking powder then stir in the hazelnuts. Add to the wet ingredients and mix well. Use an ice-cream scoop to form balls of cookie dough or weigh out 35g per cookie and roll into balls. Chill the shaped cookies overnight or freeze for later use.

Preheat the oven to 160°C. Space the cookies out on a baking tray lined with baking parchment and bake for 12–15 minutes. You can bake these straight from the freezer.

Once the semifreddo is completely frozen, use an 8cm (3in) round cutter to quickly stamp out discs. Dip the cutter into warm water between each use to get a clean, neat finish. Return the discs of semifreddo to the freezer to firm up. Any leftovers can be packed into a tub and stored in the freezer to enjoy another time.

Combine the ingredients for the jam in a large heavy-based saucepan and mix well. Leave to macerate for about 30 minutes. The sugar will start to dissolve, shortening the cooking time and giving you a fresher-tasting jam. Place the pan over a high heat and bring to the boil, then stir occasionally as it cooks. I find raspberry jam is particularly prone to spitting everywhere so be careful when you stir it.

Cook the jam to 108°C. You can also test the setting point by using the wrinkle test. Place a small plate in the freezer when you start to cook the jam. To test, drop a small amount of jam onto the frozen plate. It should immediately thicken and set and the surface should wrinkle when pushed with your finger. If it is still quite liquid, cook the jam for another 3–5 minutes before testing again. Pour into a container and store in the fridge.

Once you have prepared all the elements, you can assemble the ice cream sandwiches. Match your cookies into evenly-sized pairs then spread the underside of each one with a thin layer of raspberry jam. Once the semifreddo is firm again, sandwich a disc between each pair of cookies and gently press together to make sure it is well sealed. The semifreddo and cookie dough will last well in the freezer for up to 2 weeks but it is best to construct the sandwiches shortly before you eat them.