In a large bowl, mix together all the fritter ingredients, except the oil, until combined. For the yogurt dip, simply mix all the ingredients together in a small bowl with plenty of freshly ground black pepper and 1 tsp salt. The dip can be made in the morning and chilled.
When you’re ready to cook the fritters, heat the oil over a high heat (you want to make sure the oil is really hot, so be brave!). Carefully drop 1 tbsp of batter into the pan – add only 4-5 tbsp at a time so you don’t overcrowd the pan – and fry for about 2 mins each side until nicely crisp and golden. Remove from the pan and place on kitchen paper to absorb the excess oil. The fritters can be fried a couple of hours before serving, then reheated in the oven.
To reheat the fritters ready for serving, heat oven to 220C/200C fan/gas 7. Put the fritters on a baking tray and bake for 10 mins or until crispy and hot. Serve on a platter with the feta and spring onions scattered over, with the minty yogurt dip on the side.