Vegetable frankie

Step 1: Mix 7 oz plain flour with half of ⅜ tsp salt, 1 tbsp of 1 tbsp sunflower oil and enough ½ cup water to make a soft dough. Knead for 3 minutes until smooth, cover and rest for 15 minutes.

Step 2: Heat 1 tbsp of 1 tbsp sunflower oil in a frying pan over a medium heat and cook 1 onion for 5 minutes, until soft and golden. Stir in 1 tsp ginger-garlic paste for 1 minute, until it no longer smells raw.

Step 3: Add ¼ tsp ground turmeric, ½ tsp Kashmiri chilli powder, ½ tsp garam masala and the rest of ⅜ tsp salt, then 3 potatoes and 2 tbsp fresh coriander. Mix and cook for 3 minutes until the potato is evenly yellow and hot. Divide into 4 logs.

Step 4: Stir together 1 tbsp white vinegar, 3 tbsp water and half the 1 tsp chaat masala in a small bowl.

Step 5: Divide the dough into 4 and roll each into a thin 20 cm round. Cook on a hot tawa over a medium-high heat for 1 minute a side, brushing with the rest of 1 tbsp sunflower oil, until light brown spots appear.

Step 6: Lay a potato log across each roti, sprinkle with a few drops of the masala water, a little ½ red onion and a pinch of the remaining chaat masala, then roll up tightly. Too much masala water is the common mistake; it turns the roll soggy by lunchtime.

Step 7: Wrap the bottom half of each roll in paper or foil to serve. For the tiffin, cool completely, wrap and pack with an ice pack; eat the same day.