2 1/2 lb. russet potatoes (about 4), scrubbed, very thinly sliced
1/4 cup plus 2 Tbsp. extra-virgin olive oil
Kosher salt
4 large eggs
8 oz. hot-smoked fish (such as salmon, whitefish, or trout)
1/2 cup crème fraîche or sour cream
Trout or salmon roe, chopped dill, and thinly sliced red onion (optional for serving)

Place a rack in upper third of oven; preheat to 425°F.
Toss potatoes in a large bowl with 1/4 cup oil (using a bowl will help get the slices well coated, which means they’ll get super crisp in the oven).
Season generously with salt.
Transfer potatoes to a rimmed baking sheet and spread out into an even layer (it’s fine to have them piled on top of each other; just keep them even).
Roast, undisturbed, until browned and very crisp (top and bottom), 40–50 minutes. Let cool 5 minutes.
Heat remaining 2 Tbsp. oil in a large nonstick skillet over medium-high.
Crack eggs into pan and fry, spooning oil over whites, until set, about 3 minutes.
Divide potatoes among plates and top each with an egg, some smoked fish, and crème fraîche.