Ingredients
1/4 cup champagne vinegar
1 spring onion (bulb only) or shallot, finely chopped
Coarse salt
1 pound green asparagus
1 pound white asparagus
1 tablespoon grainy Dijon mustard
1 teaspoon fresh lemon juice
3/4 cup extra-virgin olive oil
Freshly ground pepper
4 ounces mixed tender salad greens, such as mâche and baby arugula
3/4 cup loosely packed mint leaves
8 thin slices speck (about 4 ounces)
Preparation
Bring vinegar and spring onion to a boil in a small saucepan over medium heat. Cook until liquid is reduced by half, about 2 minutes. Set aside.
Bring a medium saucepan of water to a boil; add salt. Prepare an ice-water bath, and set aside. Peel bottom 2 inches of asparagus, reserving peels. Blanch asparagus peels 2 minutes; immediately transfer with tongs to ice-water bath to stop the cooking. (Keep water at a boil.) Remove peels with a slotted spoon; set aside. (Reserve ice-water bath.) Blanch asparagus until crisp-tender, about 4 minutes. Immediately transfer with tongs to ice-water bath. Drain; set aside.
Cut lower third from each asparagus spear, and transfer pieces to a food processor. Set remaining asparagus aside. Add reserved peels, the vinegar mixture, and mustard to processor; process until smooth. With processor running, pour in lemon juice and then oil in a slow, steady stream. Pass mixture through a fine sieve into a small bowl; discard solids. Season vinaigrette with salt and pepper.
Put salad greens and mint in a large nonreactive bowl (glass or ceramic). Drizzle with vinaigrette, and gently toss. Divide asparagus among serving plates. Top each serving with dressed salad greens and a slice of speck.
