1 (10-inch) piece baguette, cut into 1-inch pieces
1/2 cup extra-virgin olive oil, divided
1 garlic clove
1 large egg
2 tablespoons fresh lemon juice
1 tablespoon anchovy paste
1 cup basil leaves, coarsely chopped
1/2 cup flat-leaf parsley, coarsely chopped
1 package romaine hearts (1 pound), leaves separated and washed well, then halved crosswise
1 cup coarsely grated Parmigiano-Reggiano
Preheat oven to 375°F with rack in middle.
Toss bread with 2 tablespoons oil and 1/4 teaspoon each of salt and pepper in a large 4-sided sheet pan, then spread out in 1 layer. Toast in oven, stirring halfway through, until golden, 12 to 15 minutes.
Meanwhile, with motor running, drop garlic into a food processor and finely chop. Add egg, lemon juice, anchovy paste, and 1/2 teaspoon pepper and pulse until combined. With motor running, add remaining 6 tablespoons oil in a slow stream, blending until emulsified. Add herbs and blend until dressing turns green and herbs are finely chopped.
Toss romaine with dressing, croutons, and half of cheese in a large bowl. Sprinkle with remaining cheese.