Pyaaz kachori

Step 1: Mix 10 ½ oz plain flour (maida), 1 tsp salt and ½ tsp ajwain (carom seeds) in a wide bowl, crushing the ajwain between your palms as it goes in. Pour in ¼ cup vegetable oil and rub it into the flour with your fingertips for 3–4 minutes, until the flour looks like damp sand and a handful holds its shape when squeezed. This step (moyan) is what makes the crust flaky, so don't rush it; too little oil gives a hard, biscuity shell.

Step 2: Add ½ cup cold water a little at a time and bring it together into a firm, slightly rough dough. Don't knead it smooth like chapati dough: you want it just combined, or the crust turns chewy. Cover with a damp cloth and rest for 30 minutes while you make the filling.

Step 3: For the filling, heat 2 tbsp vegetable oil in a frying pan over a medium heat. Add 1 tsp cumin seeds, 1 tbsp fennel seeds, 1 tbsp coriander seeds and ½ tsp nigella seeds (kalonji) and let them sizzle for 30 seconds until fragrant, then stir in ¼ tsp asafoetida (hing).

Step 4: Add 3 onions, 3 green chillies and 1 tbsp fresh ginger and cook, stirring often, for 7–8 minutes until the onions are soft, translucent and only just turning pale gold. Keep the heat moderate: browned onions turn bitter and dry in the finished kachori.

Step 5: Sprinkle in 3 tbsp gram flour (besan) and stir for 2 minutes until it smells nutty and coats the onions. It soaks up the onion juices so the filling won't leak or steam the pastry.

Step 6: Stir in 1 potato, 1 tsp Kashmiri chilli powder, 1 tsp ground coriander, 1 tsp garam masala, 1 tsp dried mango powder (amchur), ½ tsp chaat masala and ¾ tsp salt and cook for 2 minutes more, until the mixture clumps together. Take off the heat, mix in 3 tbsp fresh coriander and spread on a plate to cool completely. Warm filling softens the dough and makes the kachoris split in the oil.

Step 7: Divide the dough into 12 balls and the cooled filling into 12 portions, squeezing each portion into a firm ball.

Step 8: Flatten a dough ball with your fingers into a 9 cm round, keeping the edges thinner than the middle. Set a ball of filling in the centre, bring the edges up around it in pleats and pinch them together at the top; twist off any excess dough. Turn seam-side down and press gently with your palm into a 7 cm disc about 1.5 cm thick. Press lightly: a torn kachori fills with oil.

Step 9: Heat 1 litre vegetable oil in a karahi or deep pan over a low-medium heat to about 130–275°F. It's ready when a pinch of dough sinks, then rises slowly with a few lazy bubbles. If it shoots up sizzling, the oil is too hot.

Step 10: Slide in 4–5 kachoris and leave them alone for the first 5 minutes; they will slowly float. Fry on a low heat for 15–18 minutes in all, turning every few minutes, until they puff, the crust is evenly golden and blistered and they sound hollow when tapped. Hot oil is the most common mistake: the outside browns while the inside stays raw and the crust goes soft as it cools.

Step 11: Lift out and drain upright on a rack so the oil runs off. Fry the rest the same way, letting the oil cool a little between batches. To serve, poke a hole in the top of each kachori and spoon in 6 tbsp tamarind and date chutney, with 6 tbsp green coriander chutney alongside if you like.