Mix together lemon zest and juice, shallot, wine and 1/2 tablespoon of olive oil. Place chicken thighs in a shallow dish and pour lemon juice mixture over them. Cover and refrigerate for 2 to 12 hours.
Heat remaining olive oil in a sauté pan over medium heat. Add mushrooms and sauté until they start to release their juices, about 4 minutes. Season with salt and pepper. Remove mushrooms from pan and set aside.
Add pancetta to mushroom pan and brown over medium heat, about 5 minutes. Set aside with mushrooms.
Preheat oven to 400°F Strain the liquid from the chicken, reserving the shallots and lemon zest and discarding the liquid. Place chicken, shallots, lemon zest, onion, potatoes, thyme, mushrooms and pancetta in a roasting pan. Stir lightly to combine ingredients.
Roast for 15 minutes. Cover and continue cooking 25 to 30 minutes, basting occasionally, until juices run clear when a piece of chicken is pierced with a knife. Serve immediately.