Soak all but one handful of the bread chunks in the milk and set aside. Heat the oil in a large non-stick pan and cook the onions with the fennel and chilli flakes (if using) for 10 mins until softened. Add the garlic and the cavelo nero or kale and cook for 5 mins until softened, adding more oil if needed. Leave to cool.

Tip the onion mixture and the remaining ingredients (aside from the handful of bread) into a large bowl, season generously and use your hands to scrunch everything together really well. Scatter the stuffing into a shallow roasting tin or baking dish. Can be kept in the fridge for up to two days before baking. Top the stuffing with the remaining torn bread. To cook, heat oven to 220C/200C fan/gas 7 and bake for 30-35 mins until the top is crispy.