Place the oil and butter in a large pan and place over a medium heat.
Add the diced onion and sweat under a lid until softened stirring occasionally (about 8 minutes).
Add the diced potato and fry gently for another 2 minutes.
Then add the stock, spinach, nutmeg, salt and pepper.
Bring to the boil, reduce heat and then simmer for 15 minutes or until potato is tender.
Blend soup with a stick blender, don’t overdo it.
Garnish with a grinding of dried chillies and garlic. and serve with crusty bread.