Heat the butter in a large pan and add the parsnip cubes. Toss the parsnip cubes in the butter for 2 minutes. Add the stock, bring up to the boil and simmer for 10 minutes. Add the chopped pears, season with freshly ground black pepper and cook gently for 20 minutes more.
Cool for a few minutes, then blend the soup in a liquidiser or food processor until completely smooth. Return to the pan, stir in 50g Wensledale blue cheese and the cream or milk. Reheat gently to melt the cheese. Pour the soup into bowls and top with the remaining crumbled cheese and a few vegetable crisps.
Freezing and defrosting guidelines
Make the soup, then leave to cool at room temperature. Freeze (without garnishes or toppings) in a rigid container, leaving a bit of space for expansion, for up to 1-3 months. Reheat either from frozen or defrost in the fridge overnight. Once piping hot, add toppings or garnishes and serve.