Mix the parsley, olive oil, red wine vinegar, fresh cilantro, garlic, red pepper flakes, cumin, and salt in bowl, set aside. 

Place cubed chicken in bowl. Add 4 tbsp of prepared chimichurri sauce and marinade as grill comes to temperature. Alternatively, you can marinate for up to 24 hours in the fridge,

Heat a large, heavy skillet on high heat. 

Heat a pan over medium heat. Add the chicken cubes until cooked through to an internal temperature of 165 degrees, about 6 minutes.  

Add water to a large stock pot and bring to boil.

Generously salt water and add in pasta. 

Cook pasta to just under al dente (should be flexible but with a bit of crunch still.) 

Remove 1 cup of pasta water and add to pan with chicken, bring to a boil. 

Drain pasta and add to pan with chicken and boiling pasta water. 

Stir in 1/2 cup chimichurri sauce and toss as pasta water cooks down. 

Taste and add up to 1/2 cup more chimichurri sauce, depending on your taste. 

Garnish with parmesan cheese and serve.