Step 1

Heat the oil over medium heat in a large-ish sauté pan, add the cumin seeds and let them sizzle for 10 seconds. Add the onion, then stir and fry for five or six minutes, until they're soft.

Step 2

Add the ginger, serrano chile and turmeric and stir for a minute. Add the peas, potatoes, salt and pepper and stir and cook for two to three minutes, sprinkling with a little water if the peas get too dry.