Decorate the cake
Remove the cake from the oven and leave to cool in the tin for 10 mins before transferring to a wire rack to cool completely. To decorate, gently warm the remaining 50g marmalade in a small pan and brush some of it over the cake. Peel (removing as much pith as possible) and thinly slice 1 sweet orange, 1 blood orange and 1 pink grapefruit, removing any pips. Layer up the slices on top of the cake (you may not need them all) then drizzle over any remaining marmalade. Slice and serve with any remaining fruit slices on the side.
Calories 314 (16%), sugar 29g (33%), fat 16g (22%), saturates 9g (44%), salt 0.2g (4%), based on 12 servings.