Heat a large, lidded casserole dish over medium heat and add the oil, onions, celery and garlic. Fry for about 10 minutes, then add the pork and fry for a further 5-10 minutes.
Add the white wine and simmer until the wine is nearly dry, then add the mustard, sage, chicken stock and beans and bring to a simmer. Simmer covered for about 1 hour, then stir in the silverbeet and simmer for a further 20 minutes until the pork is tender and the stew is slightly thickened.
Stir through cream and season with salt and pepper. Remove from the heat and stand for 10 minutes, then serve scattered with parsley, parmesan and freshly cracked black pepper.
