Few ingredients work as hard in the snack kitchen as besan, which turns up everywhere from Gujarati steamers to Punjabi frying pans and is just as easy to mishandle, because what you want from it changes with the destination. A pakora needs a thick batter that clings, steamed dhokla wants a light, slightly aerated mix, and khandvi calls for a batter thin enough to spread into a sheet you can see through, yet one that still sets firm once cooked. When a pakora turns soggy, a dhokla comes out dense or a khandvi refuses to roll, the flour is rarely to blame. More often the batter was the wrong thickness for the job, or it was cooked before it had rested long enough.
Keeping lumps out from the start
Besan forms lumps whenever liquid arrives too quickly, because the outside of each clump absorbs water and seals dry flour in the middle. The reliable remedy is to whisk the flour with its spices and salt while everything is still dry, and then to add water in stages, a few tablespoons at a time with constant whisking, rather than pouring it all in together. Sifting the flour first removes clumps that already exist and helps most with besan that has been sitting in a tin and compacting. If lumps remain regardless, rub the batter through a fine sieve using a spoon; this does more than extra whisking, which usually only chops big lumps into smaller ones without dissolving them.
Reading thickness by eye
Three visual checks cover nearly every use of besan. The first is a ribbon: batter lifted on a spoon folds back onto itself and sits on top for a moment before it sinks, a texture for thicker dhokla mixes and certain stuffed pakoras. The second is a coat: batter that stays on the underside of a spoon as an even, opaque film instead of running off, which is what ordinary pakoras need. The third is a pour: batter that leaves the spoon as a thin, steady, almost continuous stream, the right state for khandvi and thinner dosa-style besan cooking. Testing against these before you start to fry or steam saves far more batter than trying to repair a poor batch afterwards.
Pakora batter and the clinging coat
Pakoras and bhajiyas want a batter heavy enough to hold on the vegetables as an even, visible layer, about as thick as pancake batter; lift the whisk and it should slide back into the bowl in a slow ribbon, never a thin stream. A thin batter fries into a flimsy, see-through shell that does not crisp, while a very thick one leaves the middle doughy and raw by the time the surface has browned. Replacing up to about one part in five of the besan with rice flour or cornflour gives a noticeably crisper result than besan alone, since it fries lighter and is less likely to soften as it cools. Resting the batter for 10 to 15 minutes before frying gives the flour time to hydrate, and a hydrated batter grips wet or oily vegetables better.
Thinner batters for dhokla and khandvi
Dhokla batter is looser than the pakora kind, closer to a medium-bodied crepe batter that you can pour, since it has to level out in the steaming tin and lift with a leavening agent, whether the quick shortcut of fruit salt and eno or a longer fermented method. Khandvi batter is thinner still, nearly like milk, because it is spread across a smooth, flat surface in the slimmest possible film and has to firm into a bendable sheet, without puffing at all. A simple trial helps: cook one small spoonful on a plate and see whether, within about a minute, it is firm enough to roll without splitting. If it stays tacky or will not curl, cook it longer or make the next batter a little thicker, since an over-thin batter lacks the structure to lift cleanly off the plate.
Correcting a batter that is too thick or too thin
A thick batter is the easier case: add water a tablespoon at a time and whisk between additions, because besan batter tightens unevenly and it is simple to overcorrect. A thin batter is harder, since tipping in more dry besan risks bringing the lumps back. Instead, make a smooth paste of a little besan and a splash of water in a second bowl, then fold it through the main batter; it disperses far more evenly than dry flour sprinkled in. If the batter has tightened up while standing, that is normal, because the flour never stops drinking liquid, and nearly every besan batter needs a last tweak of water before cooking, however good it looked at first.
Salt, acid and the timing of lift
When a besan batter relies on fermentation or a quick leavening reaction for its lift, rather than on steam alone, both salt and acid influence the timing. Salt stirred in early may hold fermentation back a little, pulling water from the batter and firming the besan proteins, so cooks who ferment a batter for several hours often add it nearer the time of cooking. Sour ingredients behave the other way: a spoonful of yogurt or lemon juice in a quick dhokla batter hastens the reaction with baking soda or fruit salt, giving livelier bubbling and a lighter crumb when time is short. After a few hours at room temperature a fermenting batter ought to look a touch puffed, dotted with small bubbles. When nothing has changed even in a warm kitchen, suspect a tired leavening agent or a cool room, and warm the bowl gently instead of simply waiting.
Resting and holding the batter
Most besan batters improve with a short rest, from 10 minutes for a plain pakora batter to 20 or 30 minutes for dhokla, which gives the flour time to hydrate and produces a smoother texture in the finished dish. After standing, particularly in a warm kitchen, the batter usually needs a quick re-whisk and a small splash of water just before use, because besan keeps absorbing liquid and settling as it waits. Pakora batter that is left over deteriorates after a few hours on the counter; if it must wait, chill it, then bring it back to room temperature and whisk once more before it goes into the oil.