Place cavatappi noodles into the cooker (cavatappi is recomended but if you prefer a different type feel free to venture out, it will turn out just as good).
Add chicken broth, heavy whipping cream, cream cheese and onion powder; mix and stir.
Place the lid on. Pressure cook on high for 3 minutes and 5 minutes natural release. Follow the manfacture instructions for a quick release.
Remove the lid. Mix well until the cream cheese completely covers the noodles.
Add buffalo sauce and the rest of the cheese (in 4-5 increments to prevent clumping); stir until cheese is fully melted and well mixed.
Season with 1 tsp salt (+/- adjust to your liking) and ¼ tsp black pepper; mix and stir.