In your soup pot set over medium-high heat, heat a drizzle of oil and spoonful of butter and saute the onion and celery for about 5 minutes, until soft. Add the pear and curry and cook a few more minutes.
Add the stock, parsnips, potato, bay leaf, salt, pepper and nutmeg. Bring to a simmer and cook until the parsnips are very tender. Puree with a hand held immersion blender (or transfer in batches to your blender) until smooth, adding the cream or evaporated milk at some point.