Cook pasta in boiling water until al dente, 7-10 minutes.
Prepare Pesto
Chop parsley and basil, including stems and set aside. Oven should be set to 350F to toast walnuts and then let cool. Place half of the oil, Parmesan cheese, garlic and walnuts into a blender. Blend to a paste consistency, stopping to scrape down the sides twice. Switch to a low speed and slowly add remaining oil.
Prepare Remaining Ingredients
Chop the oregano, including stems. Quarter the mushrooms, do not remove the stem and set aside. In a hot saute pan, drizzle oil. Add garlic and sauté for 30 seconds. Add mushrooms and sauté for 1 minute. Add yellow squash and sauté for 1 minute. Add cherry tomatoes and sauté for 1 minute. Add Swiss chard and oregano and sauté for 1 minute. Add grilled chicken, sauté until heated through. Add 2 Tbsp of water to deglaze. Add crushed red pepper, salt and pepper. Mix in cooked pasta and pesto and stir to mix and heat through.