The pakora roll is a fried fritter put into a soft roll, and like every fritter sandwich its defining problem is keeping the crisp shell crisp once the bread closes around it. A pakora is vegetable, often onion, potato, or spinach, bound in a spiced gram-flour batter and deep-fried into a knobbly, brittle piece, and the moment it is enclosed the steam coming off it has nowhere to escape, condenses against the crumb, and softens the very texture the roll was built to deliver. The whole craft is buying time against that, and the sauce is not a topping but the structural element that makes a hot, oily, intensely spiced fritter edible in one hand.
The craft is the drain, the bread, and the sauce. The pakora is drained hard off the fryer and used as fresh as the build allows, because a fritter that has sat and sweated is already soft before it reaches the roll. A soft floured roll is split and the cut faces given a layer of a cool sauce, a mint-and-coriander chutney or a chilli sauce cut with yoghurt, which both seasons against the spice and partly seals the crumb so it does not soak the fritter's oil straight through. The sauce goes on as a measured layer, not a flood: too much liquid drowns the crunch the sandwich exists for, too little and a dry, spiced fritter has nothing to carry it. The pakora is pressed only lightly, since crushing the open lattice collapses the crispness on contact, and a few salad leaves or sliced raw onion add a fresh counter to the fried density.
The variations follow the takeaway and the region. The Glasgow version is a fixture of the Scottish curry-house and takeaway scene, the roll loaded heavy with chilli or mint sauce; a wrap version folds the same fritter into a warmed flatbread, trading the crisp-bread problem for a fold that contains a looser load. Spiced potato, spinach, or paneer pakoras each change the fritter inside the same frame. The onion bhaji sandwich is the close gram-flour relative built on a different fritter, and the samosa sandwich pushes another fried snack through the same bread-and-chutney logic. Each deserves its own article rather than being crowded in here.