300 g digestive biscuits
150 g unsalted butter, melted
3 tsp powdered gelatine
½ cup water
¾ cup caster sugar
⅓ cup raspberry jam
200 g block dark cooking chocolate, chopped
3 tsp vegetable oil
- Grease a 19cm x 30cm lamington pan. Line base and sides with baking paper, extending paper 3cm above pan edges.
- Process biscuits in a food processor until finely crushed. Add butter. Process until combined. Press over base of pan. Refrigerate for 15 minutes.
- To make marshmallow, sprinkle gelatine over ¼ cup of the water in a small heatproof jug. Sit jug in a small saucepan of simmering water. Stir until gelatine is dissolved. Remove.
- Beat sugar and remaining water in a bowl of an electric mixer on a high speed for 4 minutes. With motor operating on a medium speed, beat in gelatine mixture in a thin, steady stream. Continue beating for a further 6 minutes, or until thick and fluffy.
- Stir jam in a bowl until smooth. Gently fold through marshmallow. Immediately spread over base. Refrigerate for 30 minutes, or until firm.
- To make topping, stir chocolate and oil in a medium heatproof bowl sitting over a pan of simmering water until smooth. Pour over marshmallow. Smooth over top. Refrigerate until set.
- Before cutting into squares, remove slice from fridge 15 minutes beforehand.