West Bengal; aloo posto is so characteristically Bengali that it is used as a cultural shorthand — 'the Bengali who doesn't eat posto' is a cultural impossibility in popular discourse
Aloo posto (আলু পোস্তো) is the quintessential Bengali vegetarian dish: potato pieces cooked in a paste made from posto (পোস্তো — white poppy seeds, Papaver somniferum) that coats each piece in a thick, slightly nutty, mildly sweet crust. Posto (poppy seed) is to Bengali cuisine what sesame is to Korean or tahini to Levantine — the paste-forming nut-seed that creates body and a distinct earthy flavour. The paste is made by soaking white poppy seeds in water for 30 minutes before grinding wet — dry grinding produces a gritty, dusty result rather than the smooth white paste needed for even coating. A touch of mustard oil and green chilli completes the dish.
Eaten with plain rice — the mildly sweet, nutty posto coating on the potato softens beautifully against plain rice. No strong spice is needed: the poppy seed is the sole flavour medium. A side of dal completes the simple vegetarian Bengali meal.
{"Soak poppy seeds for a minimum of 30 minutes before grinding — dry grinding leaves grit; wet-ground seeds produce the characteristic smooth, dense paste","Use white poppy seeds (সাদা পোস্তো) not blue or black — different species and different flavour profiles","Add the posto paste after the potato has partially cooked in the pan — adding it raw at the start results in the paste sticking and burning before the potato cooks","Cook covered on low heat after adding posto — this allows the paste to steam gently onto the potato without burning"}
A practitioner adds the soaked, drained poppy seeds to the potato in the pan and covers immediately — the steam from the cooking potato is enough to grind the seeds further into a paste as they cook, without the grinding step. This is the quick weekday method. For formal or restaurant preparation, pre-grind to a smooth paste. The ratio is approximately 2 tbsp posto per 200g potato. A single broken green chilli adds fragrance without excessive heat.
{"Grinding dry poppy seeds — produces a granular, dry paste that doesn't coat the potato smoothly","Adding posto paste at the beginning of cooking — it burns on the pan surface before the potato is cooked","High heat after adding posto — the paste scorches quickly; low heat and a covered pan is the technique"}