Soak the red onion slices in the 1/2 cup red wine vinegar to soften and take away some sharpness, about 30 minutes. Meanwhile, wash and dry the lettuces. Tear the leaves into bite-size pieces. In a large bowl, toss the greens with all but 3 tablespoons of the pine nuts, most of the scallions, half the cheese, half the prosciutto and all the basil and parsley. Arrange on a large platter.

In a medium skillet, slowly cook the garlic in the olive oil over very low heat 8 minutes, or until barely colored. Turn the heat to medium-high and add the vinegars to the oil. Cook a few moments, or until the acid has diffused slightly. Add brown sugar to taste and let the mixture bubble slowly 1 minute. Taste for sweet/tart balance - careful, dressing is hot. Stir in extra brown sugar or balsamic to taste. Season with salt and pepper. Set aside until ready to serve.

To serve, top the salad with the drained red onion and scatter the rest of the scallions, pine nuts, cheese and prosciutto over the salad. Reheat the dressing, stir vigorously to blend and spoon over the salad. Serve immediately.