Potato cubes stir-fried in mustard oil with a thick poppy seed paste and green chilli until completely dry and fragrant. The dry version of aloo posto — a slightly different preparation from the slow-cooked covered version, with a more roasted character.
Ingredients
4 medium potato — peeled and cut into 1.5 cm cubes
5 tbsp white poppy seeds (posto)
2 green chilli — one for the paste, one slit for cooking
1/4 tsp nigella seeds (kalonji)
3 tbsp mustard oil
1/2 tsp turmeric
salt to taste
a pinch of sugar
1 tsp raw mustard oil for finishing
Method
Soak the poppy seeds: Place 5 tbsp white poppy seeds in a small bowl. Cover with 4 tbsp water. Soak for 20 minutes until softened. Soaking makes them grind into a smooth paste more easily.
Grind the posto paste: Drain excess water from the soaked poppy seeds. Place in a small mixer jar with 1 green chilli and a tiny pinch of salt. Add 2 tbsp fresh water. Grind for 3 minutes until a very smooth, thick, creamy white paste forms. There should be no grittiness. This thicker version of the paste — slightly more concentrated than the braised version — is what makes the fry version more intense.
Heat mustard oil to smoking: Place a wide pan on high heat. Add 3 tbsp mustard oil. Heat until it just smokes. Reduce to medium. This smoking step is essential in Bengali cooking.
Add nigella seeds: Add 1/4 tsp nigella seeds to the hot oil. They will crackle within 5 seconds.
Fry the potatoes: Add the cubed potato pieces. Sprinkle 1/2 tsp turmeric over them. Stir to coat. Cook on medium heat, stirring every 2 minutes, for 8 to 10 minutes until the potato cubes are cooked through and their surfaces have turned golden and slightly crispy. Test one cube by pressing with a spoon — it should mash easily with slight resistance.
Add the slit green chilli: Add the slit green chilli to the frying potato. Stir briefly.
Add the posto paste: Add the ground poppy seed paste to the pan. Stir immediately and continuously — the paste will start sticking to the potato and coating each cube. Work fast for the first 30 seconds.
Fry together on medium heat: Keep cooking on medium heat, stirring every minute, for 5 to 6 minutes. The paste will go through stages — first it will make the mixture wet, then it will dry out and begin sticking slightly to the pan. This drying and slight sticking is correct — it creates the characteristic toasted poppy seed flavour of the fry version.
Finish: Add a tiny pinch of sugar. Add salt. Stir gently. The aloo posto fry should be completely dry — no liquid, each potato cube coated with a dry, golden posto crust.
Add raw mustard oil and serve: Remove from heat. Drizzle 1 tsp raw cold mustard oil over the top. Stir once. The raw oil adds a fresh, sharp note. Serve with steamed rice and dal.
Note: This dry version of aloo posto is the result of cooking the posto paste in a very hot pan rather than adding water and covering to steam. The result has a stronger, more roasted poppy seed flavour than the traditional moist version. In Bengal, the question of which version is better is a topic of household debate — the wet version is gentler, the dry version is more intense.