Use the fine-grating disc of a food processor to grate the potato (and parsnip if using). Squeeze the water out of the grated veg, until it is as dry as you can make it. Mix in a large bowl with the spring onion (or herbs if using).

Combine the dry ingredients together and then stir this mixture in with the veg so that everything is thoroughly coated in spicy flour. Then use your hands to mix in the milk - start with 1tbsp and only add more if the mixture isn't sticking together. It should start to feel almost like a "dough".

Form the "dough" into 6-8 hash-brown-sized patties, using your hands. Heat plenty of sunflower oil in a large frying pan. When it is very hot, fry the patties in the oil for about 3 minutes on each side. Place the cooked hash browns on some kitchen paper, to soak up any excess fat before you serve them.