Preheat oven to 375 degrees.
Peel and cut the potatoes into roughly the same size, about 2 inches. Add the potatoes to a large pot and fill it with cold water. Add a tablespoon of salt.
Bring the pot to a boil over high heat, then reduce it to a simmer. Cook for about 15 to 20 minutes or until the potatoes are fork-tender.
While the potatoes are cooking, cook the bacon in a skillet until crisp. Break it up and set it aside.
In a small saucepan, add the heavy cream, butter, and garlic powder. Heat for 3-5 minutes.
Drain the potatoes and return them to the hot pot. Let them sit for about a minute. This helps the steam escape, giving you a fluffy mashed potato.
Mash the potatoes using a potato masher.
Then add the warmed heavy cream mixture, 1 cup cheddar cheese, half of the bacon, and sour cream to the potatoes. Stir until combined. Add salt and pepper to taste.
Spread the potatoes into the casserole dish. Top with the remaining cheese and bacon.
Bake for 20 to 25 minutes.
Remove from the oven, garnish with chives, extra sour cream, and enjoy!