Preheat the oven to 200c. Boil the potatoes in salted water for 10mins, drain, place in an roasting dish, cover with oil and roast for 40mins, turning occasionally
When the potatoes are nearly cooked, cook the veg.
Heat the olive oil and 1 tbsp butter in a large, deep-sided frying pan. Add the onions and sage, after a few mins place the pork pieces a few at a time for 3-5 mins on each side until well coloured. Work in batches, as the pan must not be crowded or the meat will not form a good crust. When all cooked, place on a plate and keep warm. Throw the fried onions away.
Heat the remaining tbsp of butter in the pan and whisk in the flour. Then, whisk in the apple juice and stock, a little at a time, bring to the boil. Reduce the heat to a simmer and continue to cook and reduces a little (about 3 quarters its original volume), then add the cream along with the chopped sage and continue to cook until the sauce is thick and creamy. Season to taste.
Place the chops, roast potatoes and any veg on plates, drizzle the apple gravy over the top and serve immediately.