1In 10-inch nonstick skillet, cook prosciutto over medium-high heat 5 minutes, stirring occasionally. Reduce heat to medium. Cook 5 to 10 minutes longer, stirring frequently, until prosciutto becomes mostly crisp. Drain on paper towel.
2In large bowl, place salad greens, arugula, radicchio and vinaigrette; toss to coat. Sprinkle with prosciutto and cheese. Garnish with pepperoncini peppers.