Step 1

Preparation 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.

Step 2

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.

Step 3

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.

Step 4

Divide potatoes among plates and top each with an egg, some smoked fish, and crème fraîche. Spoon roe over and scatter some dill and onion on top.