How to Make It
Make the pickled red onions Tie the coriander seeds with the peppercorns in a cheesecloth bundle. In a small nonreactive saucepan, combine the water and sugar and bring to a simmer. Cook over moderate heat, stirring, until the sugar dissolves, about 3 minutes. Remove the pan from the heat, stir in the vinegar, wine, spice bundle and red onion julienne and let stand for 30 minutes. Strain the onions and discard the spice bundle.
Meanwhile, make the vinaigrette In another small saucepan, combine the water and sugar and bring to a simmer. Cook over moderate heat, stirring, until the sugar dissolves, about 3 minutes. Remove the pan from the heat, stir in the fish sauce, lime juice, garlic and chiles.
Fry the shallots and lotus root In a small skillet, heat 1/4 inch of the oil until shimmering. Add the sliced shallot and fry over moderate heat, stirring, until golden and crisp, 3 to 5 minutes. Using a slotted spoon, transfer the fried shallot to paper towels to drain and cool; sprinkle with salt and pepper. Repeat with the sliced lotus root.
In a large bowl, combine the green papaya with the jicama, green banana, basil and cilantro. Add some of the vinaigrette and toss to coat. Mound the salad on a platter, arrange the fish on top and sprinkle with the fried shallots and lotus root. Serve, passing the pickled shallots and lime wedges at the table so everyone can customize her own plate.