This might just be the quickest and easiest roast you will ever make. It would also make an impressive dinner party main. Prepare the mash ahead and the apples and pork fillets can be ready to simply sear and pop in the oven before serving.
1. Preheat the oven to 180°C/gas Mark 4.
2. To make the mash, place the parsnips, leek and garlic in a large pan of salted water and bring to the boil. Reduce to a simmer and cook for 15 to 20 minutes, until tender. Add the kale for the final 5 minutes of the cooking time.
3. Meanwhile, using a small sharp knife, mark a score line around the middle of each apple, then pierce the knife down through each apple and push a sprig of rosemary into each one. Smear the onion marmalade all over the apples and sit them upright on a large baking tray.
4. Toss the leaves from the remaining 2 rosemary sprigs and the fennel seeds together on a board and finely chop them. Toss a little salt and pepper through and spread the mixture out on the board. Rub 1 tablespoon of the oil all over the pork fillets and roll them in the fragrant mixture to evenly coat.
5. Heat a large ovenproof frying pan on a high heat. Add the remaining tablespoon of oil and sear the pork fillets all over for a few minutes, until golden. Transfer them to the baking tray with the apples and add 3 tablespoons of water. Roast in the oven for 15 to 20 minutes, until the pork is cooked through and the apples are sticky and softened.
6. Once the parsnips are tender, drain them well and return everything to the pan over a low heat for 1 minute to dry out. Blitz in a food processor with the butter and seasoning until smooth. Keep warm until ready to serve.
7. To serve, spoon the mash onto each serving plate. Slice the pork into 1cm-thick rounds and arrange beside the mash along with an apple. Drizzle any juices from the tray over and serve.
Tip: Any leftover pork would make a delicious sandwich filling or use it in a pasta or noodle dish the next day.