Nettle soup

INGREDIENTS

• 1 tbsp olive oil , plus extra for drizzling
• 1 onion , chopped
• 1 carrot , diced
• 1 leek , washed and finely sliced
• 1 large floury potato (Maris Piper or similar), thinly sliced
• 1l vegetable stock
• 400g stinging or dead nettles , washed, leaves picked (see tips below)
• 50g butter , diced
• 50ml double cream