Dice or rough cut pancetta. In a small frying pan, fry pancetta just until crispy. Do not over cook. Remove pancetta onto several stacked paper towels to drain. Set aside.

Prepare vegetable steamer and bring water to a boil.

While water is heating, diagonally cut the asparagus into 1-inch pieces. Place in steamer and steam for 2 minutes. Remove asparagus from steamer and immediately cool under cold running water or plunge into an ice bath to stop the cooking process. Drain.

Lightly toss asparagus and purple onion half rings together. Divide into individual serving bowls or salad plates. Top with grated Parmesan and pancetta crumbles. Allow each person to add dressing as desired.

To a blender add the lemon juice, lemon zest, sugar, salt, Dijon mustard and black pepper. With the blender running on low speed, drizzle the olive into the other ingredients to create an emulsion. Put dressing in a serving container, cover and refrigerate while preparing salad.