For rhubarb relish:
- Stir together vinegar, sugar, salt, and coriander seed in a medium glass bowl.
- Microwave until bubbling, about 1 minute. (Alternatively, heat in a small saucepan.)
- Stir to dissolve sugar and salt. Stir in rhubarb and shallot. Set aside to cool, stirring occasionally. Cover and refrigerate until needed.
For creamy herb dressing:
- Whisk together mayonnaise, oil, lemon juice, anchovy paste, and mustard in a small bowl.
- Fold in the parsley, chives, and basil. Season with salt and pepper.
- Heat oil in a large cast-iron skillet over mediumhigh heat. Add prosciutto and cook until rendered and crisp, about 3 minutes.
- Add bread cubes and toss to coat. Cook, stirring occasionally, until golden and crunchy, about 10 minutes. Season with salt and pepper.
- Pour onto a plate, and set aside until needed. Keep skillet handy.
- Preheat oven to 450 degrees.
- Place asparagus in skillet. Drizzle with oil, and roll to coat. Spread into a single layer and sprinkle with salt and pepper.
- Place in oven and toast until stems are tender and browned in spots, and tips are sizzling, approximately 8 to 10 minutes, depending on size of stalks. Meanwhile, cook eggs.
- Place eggs in medium saucepan and cover with water to a depth of 2 inches.
- Bring to a boil over high heat then remove pan from heat, cover, and let stand 5 minutes. Meanwhile, assemble salads.
- Divide creamy dressing among 4 serving plates. Top with warm asparagus spears, and then croutons. Drain rhubarb relish and spoon it around edges of the salad.
- Drain eggs and rinse under cold running water only until cool enough to handle. Do not let eggs get cold. Quickly peel warm eggs and place one atop each salad. Split each egg with a fork to reveal the warm interior, sprinkle with salt and pepper, and serve immediately.