OK - don't know how similar it will be to M&S one, but it is lovely and v easy
Ingredients
2 dessert apples
1 orange
175g / 6 oz soft marg
175g / 6 oz caster sugar
3 eggs
275g / 9oz SR flour
Set oven to 160 / 325 / GM 3
Line 8 inch deep round cake tin
Peel the apples, cut them into quarters then cut away the cores. Cut the apples into small pieces.
Finely grate the orange then cut two slices and cut each one in half.
Beat the marg and sugar together until light & fluffy.
Beat the eggs and add a spoonful of egg, then a spoonful of flour to the marg mixture and mix until smooth. Continue adding alternatespoonfuls until both have been added and the mix is smooth.
Stir in teh apples pieces and grated orange rind into the cake mixture.
Spoon mix into tin and spread top flat.
Arrange the halfed orange slices in the centre to make a pattern (you could miss this bit out, if you're going ot ice it)
Bake cake for about 1 hour until it is well risen and a skewer comes out clean when pushed into centre
Ta daaaaaa
Excuse typing, keyboard playing up a bit. Let me know if you amke it