Melt the butter with the olive oil in a large heavy-based saucepan and, in this, soften the onion and garlic over a low heat for about 10 minutes. Add the pumpkin and cook, stirring occasionally, for a further 5 minutes, then add the chickpeas, stock and bay leaf. Cook, covered, for 20 minutes.
Remove the bay leaf and roughly mash up the pumpkin and chickpeas using a potato masher to get a textured soup, or whizz it up in a blender in batches if you want it smooth, then return to the pan. Add the spinach, give it a stir and cook for 5 minutes.
Check the seasoning, adding salt and pepper, if liked.
Serve it up with a chunk of good bread.
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.