Strawberry mousse cake

1.Preheat oven to 180°C )160°C fan-forced). Grease a 22cm-springform pan and line base with baking paper. Using an electric mixer, beat cake mix, eggs, butter and milk in a large bowl on low speed for 30 seconds or until combined. Increase speed to medium; beat for 4 minutes or until mixture is pale.

2.Pour into prepared pan; smooth surface. Bake for 30 minutes or until a skewer inserted at centre comes out clean. Stand cake in pan for 5 minutes, then release sides of pan and transfer cake to a wire rack to cool. Clean pan.

3.Line base and sides of same pan with baking paper, extending paper over rim. Process half the strawberries and icing sugar until smooth; transfer to a medium bowl. Sprinkle gelatine over 1/4 cup boiling water in a small heatproof jug; stir briskly to dissolve. Stir gelatine into strawberry mixture. Chill for 10 minutes, stirring occasionally, or until thickened slightly.

4.Using a large serrated knife, level top of cake. Place cake in prepared pan. Cut sponge roll into 8 slices; trim 1cm off base of each slice to create a straight edge. Position sponge slices, trimmed-edge down, around inside rim of pan. Fold strawberry mixture through whipped cream. Pour into pan; smooth surface. Chill for 2 hours or until set. Slice remaining berries thickly, then arrange over mousse.