Peel and dice the potatoes. Thinly slice the leek and chop the garlic and mushrooms.
Heat a little oil in a saucepan and gently cook the leek for about 8 minutes, until soft.
Add the garlic and mushrooms and cook for a couple of minutes more, stirring.
Stir in the Thai green curry paste and cook briefly until fragrant, then add the potatoes.
Mix well to coat everything, then pour in the vegetable stock and add the bay leaf.
Bring to the boil, then cover, reduce the heat and simmer for 20–25 minutes, until the potatoes are tender.
Remove the bay leaf, then add the coconut cream and fresh coriander.
Blend the soup until smooth and creamy using a hand blender. If it feels too thick, add a little more stock.
Reheat gently if needed, then serve with a squeeze of fresh lime juice.
Serve hot with flatbread on the side.