Using a sharp paring knife carefully remove the cabbage core. Remove large outer leaves and set aside. Bring a large saucepan of lightly salted water to the boil. Blanch cabbage leaves in boiling water and refresh in a bowl of iced water. Dry leaves and set aside.
Using a sharp knife thinly slice remaining cabbage. Heat butter in a large heavy-based frying pan over medium high heat, add bacon and cook, stirring occasionally until fat has rendered, about 5-6 minutes, add onion and continue cooking until onion is soft, about 10 minutes.
Add pork mince to frying pan, increase heat to high and cook until pork mince begins to brown, about 5 minutes. Stir through cabbage, thyme, nutmeg and lemon rind and cook until cabbage wilts. Season to taste and set aside to cool.
Preheat oven to 150°C. On a clean work surface lay out a cabbage leaf, Using a sharp knife remove the spine and discard. Place about ½ cup of stuffing mixture into the middle and roll to enclose. Repeat with remaining leaves and filling. Place cabbage rolls into a baking dish that fits them all snuggly. Cover with chicken stock and foil. Place into the oven and bake until warmed through, about 30 minutes. Serve warm with broth spooned over.