Boston Lettuce and Radishes with a Dijon Caper Dressing Recipe

1 large head Boston lettuce
1 bunch radishes (about 8 medium radishes), thinly sliced, and some reserved for garnish
1/3 cup capers, drained
2 tablespoons finely chopped flat Italian parsley
1 clove garlic, pressed
3 tablespoons olive oil
3 tablespoons mayonnaise
2 teaspoons Dijon mustard
1 teaspoon white vinegar
Juice from ½ lemon
3 pinches of salt
10 grinds of black pepper

Remove the leaves from the lettuce and discard any browned, wilted, or holey outer leaves as well as the bitter inner leaves. Wash and dry the good leaves (see Note).
To make the dressing: Mix all the ingredients together in a bowl or shake in a sealable container until fully incorporated.
In a large bowl, toss the lettuce leaves with the radish slices, capers, chopped parsley, and most of the dressing. Divide the salad among the serving plates.