In a large pot of boiling water cook the linguine al dente.
2While the pasta is cooking heat a large skillet on medium high heat. Melt the 2 tbsp butter in the pan, season the chicken with the garlic, salt and pepper. Add 2 Tbs. of lemon juice to pan, and sear the chicken on each side then finish them off in the oven until the juices are clear.
3Meanwhile, in a food processor combine the basil leaves, garlic cloves, toasted pine nuts, 2 Tbs. of parmesan, fresh ground black pepper and olive oil. Blend all the ingredients until there are no more chunks.
In a large pot on medium heat melt the 2 tbsp butter then whisk in the flour until you get a nice smooth paste. Add the cream and stir until it thickens and boils slightly. Blend in the pesto, remaining lemon juice and the lemon zest.
Drain the linguine then transfer it to the sauce pot and stir it to coat every noodle evenly. Plate the pasta, slice the chicken into strips and divide it among the plates.