1. In a small bowl, whisk the wasabi powder with the vinegar and 1 1/2 teaspoons of water. Whisk in the peanut oil until emulsified and season with salt. Stir in the minced chives.
2. Heat 3/4 inch of vegetable oil in a small saucepan. In a medium bowl, combine the flour, ice water and egg yolk; the batter will be a little lumpy. Working in batches, dip one-third of the chive flowers in the batter and add them to the oil. Cook over moderately high heat, stirring occasionally, until lightly golden and crisp, about 2 minutes. Transfer to a rack to drain and season with salt. Repeat with the remaining chive flowers.
3. In a large bowl, toss the greens with the wasabi dressing. Season the salad with salt and pepper and mound on 4 plates. Top the salads with the fried chive blossoms and serve immediately.