Step 1

Place 2 lb. potatoes in a large pot and cover with water by 2". Add 3 large fistfuls of salt and heat over medium-high. Taste the water! It should be real salty, almost like seawater. If not, add more. Bring to a simmer. While you're waiting for the water to simmer, go ahead and get some prep work out of the way.

Step 2

Finely grate 2 oz. Parmesan with a Microplane into a medium bowl.

Step 3

Thinly slice 1 large bunch chives and transfer to a small bowl.

Step 4

Combine ½ cup sour cream and 2 Tbsp. hot sauce in another small bowl. Add a teaspoon or two of water to thin it out to drizzlable consistency.

Step 5

Line a plate with paper towels. Place 5 oz. bacon in a large 12" cast-iron skillet in as even a layer as possible and heat over medium. (We like starting bacon in a cold pan and gradually heating it—less sputtering, more crispy.) Cook until crispy on one side, 3–4 minutes. Turn with a fork and continue to cook until very crisp, 3–4 minutes more. Transfer to paper towel-lined plate to drain. Reserve the bacon-y skillet—and all of that fat!—for cooking the potatoes later on.

Step 6

It’s time to check on those potatoes. Once the potatoes come to a simmer, they need to cook until a fork or paring knife easily slides into one without much resistance, 6–10 minutes. This will really vary depending on what size and type of potato you're cooking, so keep checking them periodically for doneness. (When in doubt, cut one open and give it a taste!) Be sure not to cook them too long or they will get logged with water and fall apart. Drain potatoes and transfer to a large rimmed baking sheet or a cutting board. Let cool slightly, about 3 minutes.

Step 7

Using the bottom of a measuring cup or flat bottomed mug, smash each one gently by pressing down evenly—you want them to have flat surfaces so they'll crisp nicely, but you want them to remain mostly intact. (Some will break into more than one piece; don't worry about it!)

Step 8

Heat reserved bacon skillet over medium. If the pan isn't fully coated with bacon fat, add a good drizzle of oil—you want to make sure that there's enough fat in the pan at all times so that each potato gets a piece of the action. Arrange half of potatoes in a single layer in skillet. Season with salt and cook, undisturbed, until golden brown and crisp underneath, 6–7 minutes. Flip with a metal spatula, add 2 Tbsp. oil, and continue to cook on opposite side until golden brown and edges are crisp, 5–6 minutes more. Transfer to a platter. Heat remaining potatoes and 2 Tbsp. oil in skillet over medium. Season with salt and repeat browning and flipping process, adding more oil if the pan gets dry.

Step 9

While second batch cooks, you can begin loading your potatoes. Crumble bacon with your fingers and scatter half over potatoes. Sprinkle half of Parmesan over. Drizzle sour cream sauce over. Sprinkle half of chives evenly over.

Step 10

When second batch of potatoes is finished cooking, transfer to platter and repeat loading process with remaining bacon, Parmesan, sour cream, and chives. Season with pepper and serve.