Blackcurrant and cassis mousse cake

Method

1 Line the base of a 20cm (8in) spring-form cake tin with non-stick baking parchment. Trim the flan base to fit the tin.
2 Place the blackcurrants, sugar and cassis in a saucepan over a low heat. Stir gently until some juice is released, then cover and simmer for 4-5 minutes or until the fruit is quite soft.

3 Meanwhile, place the gelatine in a large bowl with 3tbsp cold water and leave to stand for a few minutes to soften, then pour into a small bowl and add 3tbsp cold water. Stand the bowl in a pan of boiling water and stir until the gelatine has dissolved.

4 Place the blackcurrants in a food processor and blend until smooth. Add the gelatine mixture, cream and crème fraîche and blend until smooth. Pour into a large bowl.

5 In a separate bowl, whisk the egg whites until they form soft peaks. Fold into the blackcurrant mixture, then spoon into the cake tin, cover and chill for 5-6 hours or over