2) Add another tablespoon of olive oil and 30g of the butter to the pan and heat. Add the mushrooms, carrots, celery, bay leaf and salt and pepper. Cook for 5 minutes stirring, sprinkle in the flour and cook for 2 minutes more. Whisk in 590ml of the stock, return the chicken to the pan and simmer for 5 minutes to allow sauce to thicken.
3) To make the Pesto: Place the remaining 110ml stock in a food processor with the basil, parsley, garlic, pine nuts, cheese and salt and pepper. Turn the processor on and pour in the remaining few tablespoons oil.
4) In a medium pan melt the remaining 30g butter over medium heat. Add the lemon rind and set aside.
5) Salt the cooking water and drop in the gnocchi. Cook until the gnocchi floats to the surface. Drain, add to the lemon butter and season to taste with salt and pepper. Return the pan to the heat and cook the gnocchi for 2 to 3 minutes in lemon butter until light golden at the edges.
6) Remove the cicken from the heat and stir in pesto sauce. Serve the chicken in shallow bowls and top with lemon butter dumplings.