Heat oven to 200C/180C fan/gas 6. Heat the oil in a pan and cook the onion with the pork or boar, parsley stalks, garlic, fennel seeds, chilli flakes, cinnamon, nutmeg and a pinch of salt for 8-10 mins until the mince is browned. Pour in the wine and reduce by a third, then add the tomatoes and cook for a further 3 mins or so. Add the celery and cook for 10 mins more, then add the stock and parmesan rind, if using, and part cover. Cook for 20 mins or until the celery is tender and the mix is looking rich and concentrated, but not dry, then stir through the parsley leaves.

Meanwhile, prepare the topping. Put the celeriac in a saucepan with the bay leaf. Pour over the milk and add a pinch of salt, then cover and simmer for 10-15 mins until tender. Blend the mixture in a food processor with the parmesan and crème fraîche or yogurt. Season to taste.

Pour the pork into a buttered pie dish or roasting tin. Top with the creamy celeriac topping and scatter with rosemary. Drizzle over a little olive oil, then roast for 30 mins until the top is golden.