Preheat the oven to 160C/140C Fan/Gas 3.
In a food processor beat the butter/margarine with the banana and the lemon juice and rind. Pour into a bowl.
Mix in the dried fruit and nuts or seeds.
Beat the eggs if you are using them.
Sieve which ever flours you are using with the baking powder (if you are substituting it for the eggs) and the spices.
Fold the eggs (if you are using them) into the fruit mixture alternately with the flours. Add some brandy if you like.
Line a 20cm/8in cake tin with greased greaseproof paper. Spoon the mixture in and level off the top.
Bake for about two hours or until a skewer inserted in the middle comes out clean.
Remove from the tin and cool on a rack.
Eat as it is or store to be iced for Christmas. You can also decorate this cake with whole nuts such as almonds.