Peel and finely slice onion into half moons. Cut top and bottom of courgette and discard, slice courgette into three chunks, then slice each chunk into thick matchsticks. Dice smoked chicken into small chunks.
Bring a medium-size pot of water to boil to cook the pasta. Add pasta to boiling water and cook until al dente.
While the pasta is cooking, sauté onion for a few minutes. Add courgette and sauté until soft and slightly browned. Add spinach and smoked chicken. Sauté for a few minutes, reduce heat to a low, then cover with the lid.
Mix together ricotta and pesto in a small bowl until smooth.
Remove ½ cup of the pasta water (carefully! it will be hot) and keep aside. Drain the rest of the water and pasta through a sieve.
Once the spinach has wilted turn off heat. Add pasta, ricotta-pesto mix, fresh basil and a few turns of the salt and pepper shaker. Mix well. Add and mix in enough pasta water to create a thick sauce.
Taste test and adjust salt and pepper until it tastes well seasoned to you.