New Delhi, Aug. 24 -- Cocktails have always been a canvas for innovation, but lately the brushstrokes have gone fungal. Mushrooms with their earthiness and umami-once the domain of broths and sauces-are finding fresh form in fat washes, tinctures and bitters.

In London, bartenders are tincturing porcini into gin; in Tokyo, reishi-tonic spritzes dot low-ABV menus. India's mixologists are embracing those global methods-but grounding them in local sensibility.

At the contemporary Asian restaurant Akina in Hyderabad, Bensan Varghese, corporate beverage manager at Aspect Hospitality, treats truffles not as garnish but as essence. His Forest Negroni begins with fresh black truffle emulsified with truffle oil to create a fat-wash base. Over 24...