Prep Time: 15
Cook Time: 10
Serves: Serves: 4
Heat oil in a large nonstick skillet over medium-high heat. Add onion slices; cover and cook 3 minutes. Uncover skillet; cook onions, stirring frequently, until very tender, about 10 minutes. Add vinegar; continue cooking 1 minute or until vinegar is absorbed.
Place 4 slices cheese on crust. Spread with onions; top with prosciutto strips, basil and remaining cheese slices. Bake pizza (directly on oven rack or on a cookie sheet) in a preheated 450°F oven for 10 minutes or until crust is golden brown and cheese has melted.