Remove the meat from the fridge approx. 30 mins. prior to cooking. Heat the oil in a frying pan, brown the meat all over for approx. 30 secs., season, allow to cool on a cooling rack.
Chop the onions, slice the green part into rings. Cut the tomatoes into strips. Heat the butter in the same pan and sauté the spring onions, add the tomatoes and cook for approx. 2 mins.
Stir in the breadcrumbs, pour in the wine and completely reduce the liquid. Allow the mixture to cool.
Prepare three pieces of clingfilm (each approx. 30 x 40 cm). Roughly chop the parsley, add to the mixture. Smooth out one sheet of clingfilm. Place 1/3 of the cured ham on the clingfilm (same length as a lamb loin and approx. 26 cm wide).
Spread 1/3 of the filling over the cured ham and press down gently. Place two lamb loins on top of each other in the middle of the filling.
Use the clingfilm to wrap the cured ham tightly around the lamb. Repeat this step two more times.
Remove the clingfilm. Cut the pastry in half crosswise. Place a lamb roll in the centre of each piece of pastry. Cut the fourth piece of pastry into thirds lengthwise and place one strip of pastry over each piece of meat.
Beat the egg and use it to coat the edges of the pastry. First fold in the short sides then the long sides, press down firmly.
Place the pastry parcels with the seam facing downwards on a baking tray lined with baking paper, brush with egg.
Sprinkle the pastry parcels with poppy seeds.
Bake for approx. 20 mins. in the centre of an oven preheated to 200°C. Turn the oven off and allow the lamb to rest with the oven door slightly ajar for approx. 10 mins.