In a large bowl, gently toss all of the salad ingredients except the prosciutto and basil leaves for garnish.
In a smaller bowl, whisk together the dressing ingredients, then drizzle it over the ingredients in the bowl.
Gently toss, then arrange the salad on a large platter and garnish with the fresh basil.
Slice the prosciutto in half lengthwise, then twist each piece into a spiral shape and arrange on the platter.
Add additional salt and pepper as needed and then serve.
