Bibb and Frisée Salad with Grapes and Celery

Ingredients

• 1 tablespoon champagne vinegar
• 1 1/2 teaspoons very finely minced shallot
• 1/2 teaspoon mayonnaise
• 1/2 teaspoon Dijon mustard
• 1/8 teaspoon table salt
• 3 tablespoons extra-virgin olive oil
• 1 head Bibb lettuce, torn into bite-size pieces (7 cups)
• 1 small head frisée, torn into bite-size pieces (3 cups)
• 6 ounces red seedless grapes, halved (1 cup)
• 1 celery rib, sliced thin
• 3 ounces blue cheese, crumbled (¾ cup), divided