In a large bowl, mix the grated cheddar, cream cheese, mayonnaise, chopped bell peppers, garlic powder and paprika.
Season well, add most of the spring onions and beat well to combine.
Taste and adjust the seasoning.
You can make the dip well in advance and store it in a covered container in the fridge until you're ready to serve.
Spread out the crisps on a platter and spoon the pimento dip over the top.
Sprinkle over the remaining sliced spring onions, all the sliced cornichons, the sliced green chilli, the whole pickled chillies, if using, and the chopped parsley.
Sprinkle with a few pinches of paprika and serve.
