To make the dosa pancakes
Sieve the flours, curry powder and salt into a large mixing bowl.
Whisk in the water to make a runny batter the consistency of single cream.
Leave to stand for 1 hour or overnight if possible.
To cook the dosas: Whisk the batter well before you begin to ensure the mixture is smooth and well combined. Have a large plate at the ready to stack the cooked dosas on as they are done.
Heat ½ teaspoon of sunflower oil in a medium non-stick frying pan, and pour in a small ladle of the batter, swirling it around the pan to coat evenly. Cook as you would a regular pancake crepe, using a flexible spatula to run around the edges of the dosa, checking that it is getting a golden colour on its base.
When the base of the dosa is golden carefully flip it over and cook briefly before removing to a large plate. Cook all the dosas with the remaining batter, or keep leftover unused batter for up to 3 days in the fridge.
Tip: It is very important to use a good non-stick frying pan for frying the dosas, as the batter will stick in a regular frying pan.
To make the masala dosa potatoes
Cook and dice the potatoes into 1 cm cubes.
Heat the sunflower oil in a saucepan.
Add the onion and gently fry until golden.
Stir in the ginger and chilli and fry for a couple of minutes.
Add the dhana jeeru, turmeric and amchoor and salt.
Gently stir in the potatoes, lemon juice and coriander.
Season to taste.
To make the tomato chutney
Blend the tomatoes, coriander and chilli until nearly smooth. The chutney is nice with a bit of texture.
Add a squeeze of lemon juice and a pinch of salt, adjusting as necessary. If it’s a bit sharp, you can add a pinch of sugar. The chutney is best eaten on the day it’s made but will keep for up to 3 days in the fridge.
To make the coconut chutney
Drain coconut and put into blender with herbs, chilli, salt and lime juice.
Blend until smooth.
Heat 1 teaspoon sunflower or coconut oil and carefully toast the mustard seeds until they turn a greyish colour and start to pop in the pan. Remove from the heat and stir into the coconut mix. Taste and adjust the salt and lime if necessary.
To make the green apple, coriander and mint chutney
Blend all ingredients until smooth. This chutney will be a lovely bright green just as long as you add enough lemon or lime juice.
Place a dosa on a chopping board. On the edge closest to you, place one-eight of the potato filling in a neat row, about 2 cm from the edges. Place a line of tomato chutney beside the potato, followed by the coconut chutney neatly along the line. On the furthest edge of the dosa, spread a tablespoon of the apple mint chutney. This will be the “glue” to seal the roll once you have rolled it up.
Carefully but firmly roll the clean edge nearest you over the potato, tomato and coconut filling, and gently but tightly roll all the way up. Trim both ends so that you have a neat roll then, with a very sharp knife, cut into 4 even slices. The neatest way to do this is to cut it in half first, then slice each half in half again. Wipe the blade clean on kitchen towel in between each slice to ensure clean cuts.
Serve the rolls cut-side up like sushi.