Kolkata aloo dum

Step 1: Boil 1 ⅓ lb baby potatoes in salted water for 12–15 minutes until a knife slides in with a little resistance. Drain, peel if you like (Kolkata stalls do) and prick all over with a fork. Rub with half the ¾ tsp ground turmeric.

Step 2: Heat 3 tbsp mustard oil in a kadai over a high heat until it smokes, then lower to medium. Fry the potatoes for 5–6 minutes, turning, until golden and the skins crinkle. Lift out.

Step 3: Add 2 bay leaves, 1 tsp cumin seeds, 2 green cardamom, ¾ in cinnamon stick and 1 pinch gluten-free asafoetida to the oil. When the cumin crackles and darkens a shade (about 20 seconds), stir in 1 ½ tbsp ginger paste and fry for 1 minute until it smells sweet, not raw.

Step 4: Add 2 medium tomatoes, the rest of the turmeric, 1 ½ tsp Kashmiri chilli powder, 1 tsp ground coriander, 1 tsp ground cumin, 1 ½ tsp sugar and 1 ¼ tsp salt. Cook over a medium heat, stirring, for 6–8 minutes until the masala is thick and the oil separates at the edges. Common mistake: adding water before this point; the gravy will taste of raw tomato and spice.

Step 5: Return the potatoes, pour in 1 ¼ cups hot water, cover and simmer over a low heat for 8 minutes, until the gravy is thick enough to cling and coat the potatoes.

Step 6: Sprinkle 1 tsp roasted cumin-coriander-chilli powder (bhaja masala), drizzle over a few drops of raw mustard oil if you like (or a spoon of ghee, if you don't need it vegan) and rest for 5 minutes and serve with luchi or kochuri.