Scrape the carrots and cut into large matchsticks. Top and tail the green beans, and cut in half lengthwise if fat. Shred the cabbage with a knife. Trim the cauliflower and cut into bite-size bouquets.
Stir together the mustard seeds, garlic, ginger and turmeric. Heat the oil in a saute pan and gently fry the shallots for 2 minutes to soften slightly. Add the spice mixture and cook for 1 minute. Toss in the remaining vegetables for just 1 minute. Remove from the heat, toss in the vinegar and let sit for 15 minutes, or, even better, several hours. (It keeps in the refrigerator for several days.) Taste and correct the seasonings. Serve at room temperature with crusty bread.