Potato, Pea & Leek Pancakes

white, floury potatoes (about 2 medium), peeled

salt

large leek (, halved and sliced into 3mm thick strips)

olive oil (, plus extra for frying)

+ 1 tbsp) vegetable stock or milk

eggs

black pepper

gram flour (chickpea flour/besan)

sprigs of fresh thyme (, leaves picked)

baking powder

frozen petits pois ((baby peas), defrosted)