Heat half the olive oil in a large saucepan and cook beef over high heat in 3 batches until well browned. Transfer to a plate.
Reduce heat to medium and add remaining oil and onion. Cook for 5 mins, until soft.
Add tomato paste and paprika and sprinkle flour over. Cook, stirring, for 1 min.
Gradually add stock and water, stirring constantly.
Return meat to the pan, cover and bring just to the boil.
Reduce heat to very low and cook gently, partially covered.
After cooking for the initial half hour add the carrot, potatoes and cook for a further hour.
Add the mushrooms and beans and cook, stirring often for 15 minutes.
Serve topped with a dollop of sour cream.
