Add the chicken broth, minced garlic, salt and pepper to a 6 quart Instant Pot. Stir to combine. Then add in the sliced potatoes. Seal and cook on high pressure for 2 minutes and then do a quick release to release the pressure from the instant pot after the cook time.
Preheat the oven to 375 degrees F.
Carefully remove the sliced potatoes from the Instant Pot into an oven safe baking dish. Leave the rest of the liquid in the instant pot.
Then switch the instant pot to the sauté setting and whisk in the cream. Let the cream mixture simmer in the instant pot for 2-3 minutes. Then turn the instant pot off and stir in 2 cups of the shredded cheddar cheese. Stir until melted.
Pour the cheese sauce over the potatoes in the baking dish. Gently toss the potatoes to cover it with the cheese sauce. Then top with the remaining cheddar cheese and the shredded Parmesan Cheese.
Bake for 15-20 minutes until the potatoes are warm and tender (check every 5 minutes or so). Then broil the top of the potatoes for 1-2 minutes to brown the top of the potatoes.
Let the potatoes sit for 10-15 minutes and then they are ready to serve and enjoy!
Notes
Use freshly shredded cheeses so that it melts smoothly and evenly in this recipe. Try to slice the potatoes as even as possible so that they cook at approximately the same time (the thinner the better). Refrigerate any leftovers in an airtight container for up to 5 days.