1.Stir the water and sugar in small saucepan over heat, without boiling, until sugar dissolves; bring to a boil. Reduce heat, simmer, uncovered, without stirring, 5 minutes.
2.Blend or process raspberries, juice and hot sugar mixture until smooth.
3.Push mixture through fine sieve into 20cm x 30cm lamington pan; discard seeds. Cover with foil; freeze until firm.
4.Chop frozen berry mixture coarsely. Blend or process with egg whites until smooth and paler in colour. Return mixture to pan, cover; freeze until firm.
This recipe can be made a week in advance. Raspberries may be replaced with any other berry. If using an ice-cream churner, combine fruit puree with egg whites; churn following manufacturer’s instructions.Note