Batata Vada (Spiced Potato Balls in Chickpea Batter)

Variations

• Vada pav: the vada, straight from the oil, in a split pav with dry garlic chutney — Mumbai's own snack. The bread is what the Portuguese left behind, which is why it is a soft fermented roll rather than an Indian flatbread.
• Bonda: South India calls much the same thing a bonda, sometimes with coconut or cashew in the filling.
• Other fillings: crushed peas, or a whole boiled egg wrapped in the potato. Either way the condition is the same — it has to be dry.
• Air fryer: 200°C for 12 minutes. The shell is not as light, because the air story below only finishes in oil.
• Beside samosa: practically the same filling, a different shell. That one difference reverses the oil temperature — see below.

Tips

• This is the batter you beat hard. Deep frying says a wet batter must be deliberately under-mixed, because mixing develops gluten into a chewy jacket — and files this batter as the one where that premise is absent. As farinata puts it about the same flour, chickpea flour has more protein than wheat and forms no gluten whatever, because pulse proteins are storage globulins that cannot link up. So "mix less" means nothing, and what does the work is the air you beat in. Two minutes of whisking visibly pales the batter; that is the air.
• The oil has to be hot, and that is the reverse of samosa. That page says starting in barely-warm oil "is the whole technique", because a pastry has to cook through before it colours. A batter has the opposite problem: if it does not set on contact it slides off the ball. Same potato, different shell, opposite temperature.
• Cool the filling completely. Steam out of warm potato has nowhere to go and pushes the shell apart. Samosa gives the same instruction for the same reason.
• Crush by hand, never with a masher. Crushed cells release starch, the filling turns gluey, and it fries heavy. Coarse lumps are what make it crumble in the mouth.
• A pinch of bicarbonate, no more. A little makes the batter puff and lighten; too much tastes of soap and drinks oil. Besan carries saponins and foams a bit in water on its own — that foam does not need skimming here.
• Mustard seeds open only by popping. Straight out of blooming spices — and note the difference from rasam, which pours the same tadka over the top at the end while this one folds it through the potato.
• Pull them at pale gold. The filling is already-cooked potato, so frying has nothing to cook; its only job is to set the shell. Taken to a deep brown, the besan turns bitter.