Preheat the oven to gas 6, 200°C, fan 180°C. Put the potatoes on a baking tray and cook for 40 minutes, or until tender.
Meanwhile, heat the oil in a large frying pan over a medium-high heat. Add the onion and cook for 5 minutes, until softened, adding the garlic for the last 2 minutes.
Stir in the mince and cook for 10 minutes, until browned, then add the cinnamon, olives and spinach. Cook for 5 minutes, or until the spinach has wilted, then stir in the feta and parsley. Halve the potatoes lengthways and serve with the mince filling.
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