Preheat oven to 375°F.

In a 10-inch cast-iron skillet (or 9-inch ovenproof sauté pan), heat 1 tablespoon oil over medium heat, then add the butter.

Once the butter has melted, add the garlic and crushed red pepper flakes and sauté until the garlic is translucent, 1 to 2 minutes, stirring frequently and being careful to not let the garlic burn.

Add the kale and sauté until bright green and wilted, 3 to 5 minutes. Remove the kale from the pan, removing as much of the garlic from the bottom of the pan as possible to avoid overcooking and set aside.

Add the remaining 1 tablespoon of oil to the pan, swirl to coat, then cover the bottom of the pan with potato rounds, overlapping slightly as needed. Place over medium heat for 5 minutes. Return the kale to the pan, spreading it evenly over the layer of potatoes. Add ½ cup of the vegetable broth, then crack the eggs into the pan, side by side, on top of the kale. Season with salt and pepper.

Place the pan, uncovered, in the oven and bake until the eggs are set and the yolks are still runny, approximately 7 to 10 minutes. Add additional broth if the pan seems to be drying out.

While the pan is in the oven, whisk together the crème fraîche, lemon zest and juice, and season with salt and pepper.

To serve, slice into 4 to 6 wedges, using a spatula to remove each slice. Top with a dollop of the lemon–crème fraîche and a sprinkle of scallions or chives.

Note: To parboil peeled whole potatoes, bring a pot of salted water to a boil, then carefully add potatoes. Boil until easily pierced with a fork, 15 to 20 minutes. This can be done a day in advance. Store cooled potatoes in an airtight container in the refrigerator until ready to use.