Begin by cooking the pancetta until it is crisp. Drain the pancetta on a paper towel. Sauté the onion and lemon zest in the oil from the pancetta, until the onion is translucent.
Wash and remove the ends of the asparagus spears while the pancetta is cooking. If you’re not finished, complete cleaning the asparagus and removing the ends while the onion and lemon are cooking out.
Make a basket with tinfoil that is big enough to hold all of your asparagus. Be sure that you turn up the edges so that it forms a boat or bowl and no liquids can get out.
Throw the pancetta in with the asparagus.
In a small bowl whisk together the oil, lemon juice, vinegar, honey, and sautéed onion and lemon. Pour over the asparagus and then seal the packet tightly.
Grill over direct heat for 15 to 20 minutes, until the asparagus is tender to the fork.
Pour all of the asparagus and liquid into a serving dish and serve hot with your favourite meal.