Roughly mash the vegetables together. You can also whiz to a rough paste in a food processor. Place the spinach in a colander, pour over a kettleful of boiling water until wilted. Then drain. Place in some kitchen paper and squeeze out excess water.
Stir the mashed roots together with the spinach and spring onions. Use your hands to form into 4 cakes. Place the flour on a plate. Dip each cake into the flour and shake away any excess.
Heat the oil in a large nonstick frying pan. Add the cakes and cook for 3-5 mins on each side until golden and crisp all over. Serve with a poached or fried egg alongside.
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If serving vulnerable groups, elderly people, toddlers, pregnant women and people who are unwell, cook eggs until the whites and yolks are solid.