Cook the linguine in a large pot of boiling water according to the packet instructions. Drain, reserving 125ml of the cooking water.
While the pasta is cooking, combine the coriander, peanut butter, soya sauce, honey, vinegar, sesame oil, garlic and mirchi powder in a food processor. Process until smooth. Transfer to a large bowl.
Whisk in the reserved pasta cooking water. Add the linguine, carrots, celery and green onions, and toss. Chill for at least 1 hour before serving.
Some more ideas
*Add blanched cauliflower or broccoli florets to the pasta and vegetable mixture. *Serve this dish warm by heating the sauce, then add cubes of cooked meat/paneer.
The pasta cooking water, which carries some of the pasta's starch, is used here to stretch the sauce. It's a traditional Italian technique for thinning or smoothing a sauce so that it coats the pasta evenly. And the water replaces what might otherwise be oil or other fat.