First, start by chopping your chicken breasts into 1 inch cubes.
In a bowl, season the chicken breasts with salt, ranch seasoning and crushed red pepper flakes.
Next, set the Instant Pot to the saute function. Add corn or vegetable oil to the pot. Once the oil heats up, add in the cubed chicken breasts.
Saute the chicken until golden. This should take about 3-4 minutes. Remove the chicken breasts from the instant pot and transfer them to a plate. Cancel the saute function.
Add 1/2 cup of the water to the Instant Pot and use a wooden spoon to deglaze the bottom of the pot.
Add in the rest of the water, chicken, macaroni pasta, butter, buffalo sauce and more salt to taste. In that order! Do not stir.
Close the lid and cook on high pressure for 4 minutes.
Once the buffalo chicken mac and cheese is finished cooking, do a quick release little by little until water stops spewing out. Then fully engage the quick release button to finish releasing all of the pressure.
Open the instant pot lid and add in the cream cheese, mozzarella cheese, sharp cheddar cheese and heavy cream. Stir everything together until all of the cheeses have melted and incorporated into the mac and cheese.
Top off with panko bread crumbs and parsley if desired and enjoy.