White Bean and Tuna Salad with Radicchio Recipe

1 medium head of radicchio, cored, leaves coarsely torn
6 tablespoons Parsley Vinaigrette, divided, plus more for drizzling
Kosher salt and freshly ground black pepper
2 15-ounce cans cannellini (white kidney) beans, rinsed, drained
2 celery stalks, peeled, sliced thinly on an extreme diagonal
1 cup drained olive oil-packed tuna in a jar or good-quality canned tuna, broken into large pieces
Flat-leaf parsley sprigs (for garnish)

Place radicchio in a large bowl; drizzle with 3 tablespoons Parsley Vinaigrette and toss to coat. Season radicchio to taste with salt and pepper. Transfer to a serving platter, spreading out in an even layer. Combine 3 tablespoons Parsley Vinaigrette, cannellini beans, and celery in the large bowl; toss to coat. Season to taste with salt and pepper. Arrange bean mixture on top of radicchio. Top salad with tuna and garnish with parsley. Drizzle some vinaigrette over.