In tropical Vietnam, cauliflower is a prized cool-weather crop that’s typically stir-fried, added to soup, or pickled. Home ovens are uncommon in Vietnam, so few people roast cauliflower. In my California kitchen, however, I coat cauliflower wedges in salty-sweet-spicy seasonings typically reserved for Cantonese-style char siu barbecue pork, and then high-heat roast them. The contours of the wedges caramelize here and there to develop a deep savoriness that evokes the prized edges and corners of char siu pork. Serve this cauliflower as a satisfying main dish or tuck it into bao and banh mi.