Heat a high-sided skillet over medium heat with the EVOO, about 2 turns of the pan. Add the pancetta and cook for 3-4 minutes, until it starts to get golden.
Add the mushrooms, onion, carrots and bay leaf to the pan. Saut 4-5 minutes, until the onions start to get tender, then add the garlic and cook another minute or so. Season the veggies with salt and freshly ground black pepper, and add the shredded rotisserie chicken to the pan. Pour in the chicken stock and stewed tomatoes, and bring up to a bubble.
Once the stew has come up to a boil, add in the gnocchi and cook according to package instructions. (Theyll sink at first -- wait until they come up to a float and stay floating for a few minutes. Test them for doneness by tasting one, they should be very tender and have the texture of a dumpling.) Once the gnocchi are done, remove the pan from the heat, stir in the basil and serve with the grated Parmigiano-Reggiano at the table.