Using the coarse side of a box grater, grate the potatoes and transfer them straight into a large bowl of cold water to prevent discoloration.

Lift the grated potato from the water and drain in a sieve; rinse under cold running water until it runs clear. Spread the drained potato onto a clean tea towel and wring out as much moisture as you can so the mixture becomes loose and relatively dry.

Combine the dried grated potato, finely chopped onion, self-raising flour and beaten eggs in a large bowl. Add the thyme or rosemary and season generously with salt flakes and freshly ground black pepper, mixing until evenly incorporated.

Pour enough olive oil into a heavy-based frying pan to reach about 1.5 cm depth and heat over medium-high until hot but not smoking. Drop heaped 1/3-cup portions of the potato mixture into the pan, leaving space between each fritter.

Shallow-fry the fritters in batches for about 5 minutes per side, or until a deep golden crust forms on each side and the centers are cooked through. Transfer to a wire rack to drain and season immediately with salt and pepper.

Serve hot with avocado wedges, a dash of hot sauce and/or sour cream, or make smaller rounds to use as canapé bases.