Jam Roly-Poly

1. Put a deep roasting tin on the bottom shelf of the oven, with another shelf directly above it. Pull the tin out, fill it two-thirds with boiling water, then slide it back in. Heat the oven to 180C/160C fan/gas 4. Tear off a large sheet of foil and one of greaseproof paper (about 30 x 40cm), sit the greaseproof on the foil, and butter it.
2. Tip the butter, flour and vanilla seeds into a food processor and pulse until the butter disappears, then tip it into a bowl. Stir through the suet, pour in the milk, and bring it together with a cutlery knife into a sticky dough, adding a drop more milk if it needs it.
3. Turn the dough onto a floured surface, pat it together, then roll it out to a square of roughly 25 x 25cm. Spread the jam over it, leaving a gap along one edge, then roll up from the opposite edge. Pinch the jam-free edge into the dough and pinch the ends shut. Lift it onto the greased paper, join-side down, loosely bring the paper and foil around it, and scrunch the edges to seal, leaving room for it to puff.
4. Lift the parcel onto the rack above the water tin and cook for 1 hour.
5. Let it settle for 5 minutes, then unwrap, slice thickly, and serve with custard.

Tips from the ZestyPlate Kitchen

• Handle the dough gently. Suet pastry turns tough if you overwork it.
• Leave a clear border when you spread the jam so it doesn't all squeeze out as you roll.
• Wrap the roll loosely in greased paper and foil, giving it room to puff up as it cooks.
• Steaming it over a tray of water in the oven keeps it lovely and moist.