Bring a large pot of salted water to a boil and cook the spaghetti according to package instructions until al dente. Drain and set aside.

Heat a little olive oil in a large skillet. Add the onion and garlic and sauté until softened and fragrant.

Add the chicken pieces to the skillet. Season with salt and pepper and cook until golden brown and fully cooked through.

Stir in the pistachio pesto and cream. Bring to a gentle boil, then let it simmer for a few minutes to thicken slightly.

Add the drained pasta to the skillet with the pistachio cream sauce and chicken. Toss well until all the pasta is coated in the sauce.

Divide the pasta between plates, top with fresh arugula, and garnish with pistachios. Enjoy!