Put a deep roasting tin onto the bottom
shelf of the oven, and make sure that
there’s another shelf directly above it.
Pull the roasting tin out on its shelf, fill
two-thirds with boiling water from the
kettle, then carefully slide it back in. Heat
oven to 180C/160C fan/gas 4. Tear off a
large sheet of foil and greaseproof paper
(about 30 x 40cm). Sit the greaseproof on
top of the foil and butter it.
Tip butter, flour and vanilla seeds into a
food processor; pulse until the butter has
disappeared. Tip into a mixing bowl. Stir
through the suet, pour in the milk and
work together with a cutlery knife until
you get a sticky dough. You may need a
drop more milk, depending on your flour.
Tip the dough out onto a floured
surface, quickly pat together to smooth,
then roll out to a square roughly 25 x
25cm. Spread the jam all over, leaving a
gap along one edge, then roll up from the
opposite edge. Pinch the jam-free edge
into the dough where it meets, and pinch
the ends roughly, too. Carefully lift onto the
greased paper, join-side down (you might
find a flat baking sheet helpful for this),
loosely bring up the paper and foil around
it, then scrunch together along the edges
and ends to seal. The roly-poly will puff
quite a bit during cooking so don’t wrap
it tightly. Lift the parcel directly onto the
rack above the tin and cook for 1 hr.
Let the pudding sit for 5 mins before
unwrapping, then carefully open the foil
and paper, and thickly slice to serve.