Start by making the filling. Heat the oil in a frying pan over a medium heat and cook the onion for 20 mins until soft, golden and starting to caramelise. Add a splash of water if needed (if the onion looks like it’s starting to burn). Tip into a large bowl and set aside to cool.

Meanwhile, cook the rice in a pan of boiling water for 10-12 mins until just al dente. Drain and tip into the bowl with the onions. Set aside to cool.

Soak the slice of bread in just enough water to cover it for 5 mins, then squeeze out any excess liquid. Add to the cooled onion and rice along with 1 tsp salt, 1 tsp pepper and the remaining filling ingredients. Mix using your hands until everything is well combined. Chill the mixture while you prepare the sauerkraut.

Unroll the leaves and rinse under cold water (don’t pat dry; it makes them easier to roll if a little damp). Trim away the thick stem at the base of each leaf, so you're left with a small A-shaped gap. Turn in the sides of that A to create a whole leaf shape again. Set aside the trimmings for later. Aim for around 34–36 leaves in total. Set aside any remaining leaves with the stem trimmings.

Put roughly 1 tbsp of the filling mixture at the base or widest part of each leaf and press into a roughly 5cm long sausage, leaving a small gap at each edge. Roll tightly once or twice, fold in the sides, then continue rolling to seal. Arrange the rolls seam-side down on a plate or board. If your rolls seem loose, you may have added slightly too much filling. Repeat with the remaining leaves.

Shred the cabbage trimmings plus the remaining cabbage leaves and sprinkle over enough to cover the base of a large, wide ovenproof casserole dish or pan. Arrange the stuffed rolls on top in a circular pattern, nestling them snugly together so they hold their shape during cooking. Add in a second layer if needed, tucking the diced pancetta in between the rolls. Sprinkle over any remaining shredded cabbage.

In a large jug, mix together the tomato purée, paprika and dill or thyme. Gradually whisk in 750ml water until combined. Pour the liquid over the rolls, cover the pan with a lid and bring to a boil over a medium-high heat. Turn down the heat to low and simmer gently for 3 hrs until the rolls are very tender, shaking the pan occasionally to stop the rolls from sticking. For a lightly caramelised finish, uncover the pan and cook in an oven heated to 180C/160C fan/gas 4 for the final 30 mins.

Serve with creamy polenta, soured cream, pickled chillies and a sprinkling of fresh dill. Sarmale can be served straightaway but even better the next day. Reheat gently on the hob for about 45 mins.