How to Make It
Make the chutney In a blender, puree all of the ingredients until smooth. Strain through a fine-mesh sieve set over a medium bowl; discard the solids. Season the chutney with salt and pepper.
Make the squid In a large enameled cast-iron casserole, heat 3 inches of oil to 350°. In a large bowl, whisk the tempura flour and ice water until smooth. Spread the rice flour in a shallow bowl. Working in 3 batches, dip the squid in the tempura batter, then dredge in the rice flour and shake off any excess. Add the squid to the hot oil and fry until golden and crisp, 1 to 2 minutes. Using a slotted spoon, transfer the squid to a paper towel–lined plate to drain; season with salt. Transfer to a platter and sprinkle with chaat masala and scallions. Serve with the chutney.
Tempura and white rice flours can be found at Whole Foods and on amazon.com.