In a food processor, coarsely chop 3 large garlic cloves and 4 anchovy fillets. Add 1 hard-boiled egg yolk, 1/2 cup extra-virgin olive oil, 3 tablespoons lemon juice, 1 1/2 teaspoons Worcestershire sauce, 1 teaspoon dry mustard and 1/4 teaspoon each salt and pepper; process until smooth. In a large serving bowl, toss 2 heads of romaine, torn, with the dressing and 1/3 cup grated parmesan.
