Cook the pasta according to package instructions until al dente.
Prepare the basil pesto by combining basil, garlic, pine nuts, and Parmesan in a food processor.
With the processor running, slowly drizzle in the olive oil until the mixture is well combined.
Season the pesto with salt, pepper, and lemon zest if using.
In a skillet, heat a drizzle of olive oil over medium heat and sauté the diced chicken until cooked through.
Once the chicken is cooked, add the cooked pasta directly to the skillet.
Add the pesto to the pasta and chicken, tossing to combine thoroughly.
Gently fold in the cherry tomatoes if using, and season with additional salt and pepper to taste.
Serve immediately, garnished with extra Parmesan if desired.