Zest and juice half of the lime. Add half the juice to a bowl and whisk with the vinegar. Add a pinch of salt and 1 tbsp oil. Thinly slice the mushrooms. Peel and finely chop the red onion and garlic.
Place the mushrooms, onions and garlic in the bowl with the marinade. Mix well, giving a good coating to all the veg. Set to one side. Peel and finely slice the shallots.
For the pancakes, tip the flour into a bowl. Add 1 tsp each of garam masala and turmeric. Add a pinch of salt. Pick the leaves from the coriander. Set aside. Finely chop the stalks and add in to the pancake mix along with the shallots.
Make a well in the centre and pour in the coconut milk. Add 200 ml cold water and whisk to create thin batter. Turn the oven to its lowest setting.
Heat 1 tsp oil in a large frying pan. Pour in 1 ladle of batter and move around the pan to thinly coat it.
Cook for 2 mins then flip over, cooking for a further 2 mins. Place onto a plate in the oven to keep warm. Repeat with the remaining batter, adding more oil each time.
Place a couple of pancakes on each plate and fill with the pickled mushrooms. Top with coriander leaves. Cut the saved lime into wedges and add these too. Wrap and serve.