Place the bacon in a large, deep saucepan or casserole pot, and cook over medium-high heat, stirring to turn pieces occasionally, until evenly browned, about 10 minutes. Drain the bacon pieces on kitchen paper. With another piece of kitchen paper, wipe the bacon dripping out of the pan but keep as much of the brown bits as possible. Stir in the sauerkraut, dark brown soft sugar and chicken stock, stirring to dissolve the sugar. Add the potatoes and apple slices.
Place the juniper berries, peppercorns, cloves, parsley and bay leaf into a small square of muslin, and tie the ends together to make a spice bag (or place the spices into a stainless steel tea ball). Place the spice bag into the pot, and add the pork chops and sausage pieces. Add more chicken stock, if needed, to just cover the ingredients. Bring to the boil, reduce heat and simmer until the potatoes are very tender, about 1 hour.
To serve, use a slotted spoon to remove the sauerkraut, potatoes and apple slices to the centre of a serving platter. Arrange pork chops and kielbasa pieces around the outside of the platter.