- 1 tablespoon unsalted butter
- 1/4 pound baguette, crust removed, bread cut into 1/2-inch dice (1 cup)
- 1 large egg
- 10 anchovy fillets
- 2 tablespoons fresh lemon juice
- 1 tablespoon red wine vinegar
- 1 small garlic clove
- 1 tablespoon plus 1 teaspoon Dijon mustard
- 1 tablespoon Worcestershire sauce
- 1/3 cup extra-virgin olive oil
- Salt and freshly ground pepper
- 1/4 red onion, coarsely chopped (1/4 cup)
- 2 tablespoons capers, drained
- 2 tablespoons coarsely chopped flat-leaf parsley
- 1 tablespoon prepared horseradish
- 3/4 teaspoon hot sauce
- 1 pound ground lean top round or sirloin
- 2 teaspoons canola oil
- 1/2 pound romaine lettuce, torn into bite-size pieces (8 cups)
- Melt the butter in a large skillet. When the foam subsides, add the diced baguette in an even layer. Cook over moderate heat until browned on the bottom, about 3 minutes. Stir and cook until evenly browned and crisp, about 2 minutes longer. Transfer to a plate.
- Cook the egg in boiling water for 2 1/2 minutes; drain, then scoop the egg out of the shell into a blender. Add 6 of the anchovies, the lemon juice, vinegar, garlic, 1 teaspoon of mustard and 1 teaspoon of the Worcestershire sauce. Slowly add the olive oil and blend at medium-low speed until it is incorporated and the mixture is creamy. Pour the dressing into a small bowl and season with salt and pepper.
- In a food processor, finely chop the 4 remaining anchovies with the onion, capers, parsley and horseradish. Transfer to a large mixing bowl. Add the remaining 1 tablespoon of mustard, 2 teaspoons of Worcestershire sauce, the hot sauce and ground beef and mix well. Form the meat into 12 patties and season them with salt and pepper.
- Heat 1 teaspoon of the canola oil in a large, heavy skillet. Add 6 of the burgers and cook over high heat for about 1 minute on each side for rare, and about 30 seconds longer on each side for medium rare. Transfer to a plate. Repeat with the remaining 1 teaspoon of canola oil and 6 burgers.
- In a large bowl, combine the romaine lettuce with 1/2 cup of the dressing and the croutons and toss to coat. Mound the salad on plates and set 3 burgers on each salad. Drizzle the remaining dressing over the salads and serve.
The dressing can be refrigerated for 2 days.