Heat the oil in a saucepan, add the onion and celery and fry gently for 5 minutes.
Add the butternut squash and fry for a further 5 minutes.
Add the prepared vegetable stock, bring to the boil and simmer for approximately 25 minutes until the squash is tender.
Transfer the soup to a blender or food processor (or use a hand blender in the pan). Blend until smooth.
Add the cottage cheese and blend again, adjusting the consistency if necessary.
Season to taste. Serve hot with a swirl of crème fraîche or natural yogurt.
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.