Fry the onion, garlic and parsnip in oil and butter for 5-10 minutes, stirring occasionally.
Stir in the garam masala and chilli and cook for 30 seconds.
Stir in the flour and cook for another 30 seconds.
Add the stock, bring to the boil and simmer for 10-20 minutes (until the parsnip is cooked).
Stir and mash some of the parsnips up a bit.
Add lemon juice and black pepper to taste.