This satisfying salad is great alongside broiled fish, roast chicken, or a simple steak. To turn it into a vegetarian meal, fold in sliced hard-boiled eggs.
Blend anchovies, oil, capers, and 1 cup parsley in a blender until a coarse purée forms. Transfer to a large bowl, mix in 1/4 cup vinegar, and season with salt, pepper, and more vinegar, if desired.
Add radishes, scallions, beans, olives, and remaining 1 1/2 cups parsley to bowl and toss to combine.
DO AHEAD: Salad can be made 4 hours ahead. Cover and chill.
