Very lightly butter a 1-litre pudding
basin. Heat oven to 180C/fan 160C/gas 4.
Coarsely grate one of the apple quarters
and thinly slice the rest. Combine the
sliced apple and blackberries, toss with
the 2 tbsp caster sugar and spoon half
into the bottom of the basin.
Mix together the flour and baking
powder. Beat both the sugars and butter
together in a large bowl with an electric
hand beater until light and creamy. Break
in 1 egg and beat well, then beat in the
second egg (the mix will look curdled).
Sift half the flour mixture over the sponge
mixture and fold in gently. Carefully stir in
half the milk, then repeat with the rest of
the flour and milk, followed by the orange
zest and reserved grated apple.
Spoon two-thirds of the sponge mixture
over the fruit mix in the basin and level off.
Spread the rest of the fruit on top, followed by
the remaining sponge mix. Place the basin in
a small roasting tin half filled with hot water.
Bake for 1¼ hrs (lay foil over the top for the
last 15 mins if it is browning too quickly) until a
skewer inserted in the middle comes out clean.
While the pudding is baking, make the
custard. Mix the sugar, custard powder and
cornflour with 1 tbsp of the milk to make a
paste. Beat in the egg yolk. Pour the remaining
milk into a pan, slit the vanilla pod lengthways
and scrape in the vanilla seeds. Add the pod
to the milk and bring just to the boil. Pour this
over the cornflour mix, stir, then pour into a
clean pan. Cook over a medium heat, stirring
all the time, until it is thick enough to coat the
back of a spoon. Remove from the heat and
stir in the crème fraîche.
Loosen pudding from the sides of the basin
with a round-bladed knife and carefully invert
it onto a serving plate. Serve with the custard.