Add the potatoes, onion, garlic, salt and pepper to a 6 qt. or larger Instant Pot. Cover with the 6 cups of chicken broth, stir.

Put on the lid and set to seal. Cook on high pressure for 9 minutes. After the 9 minutes, do a quick release on the pot.

In a small bowl, whisk the 3 tablespoons of flour into the cold half and half until smooth. Be sure to whisk thoroughly to remove all lumps.

After all pressure is released, remove the lid from the Instant pot and stir in the half and half mixture until well blended.

Add the cheeses and stir gently until melted.

Garnish with more shredded cheddar, crumbled bacon, and green onion, optional.