Arrange half of prosciutto on a paper towel-lined microwave-safe plate; cover with a paper towel. Microwave at HIGH 2 minutes or until crisp. Repeat procedure with remaining prosciutto. Break prosciutto into large pieces.
Whisk together mint and next 5 ingredients.
Toss greens and chopped melon with vinaigrette, and top with cooked prosciutto, crumbled feta cheese, and chopped pistachios.