for 4 servings
3 tablespoons unsalted butter
½ medium white onion, thinly sliced
1 teaspoon kosher salt, divided, plus more to taste
3 cloves garlic, minced
½ teaspoon red pepper flakes
¼ teaspoon nutmeg
2 tablespoons all purpose flour
1 cup vegetable stock (240 mL)
¾ cup heavy cream (180 mL)
¾ cup parmesan cheese (80 g), freshly grated, plus more for sprinkling
20 oz frozen spinach (570 g), thawed and squeezed dry
2 teaspoons fresh lemon juice
4 large eggs
½ teaspoon black pepper, freshly ground
toast, for serving
1. Melt the butter in a 9-inch (23 cm) cast-iron skillet over medium heat. Add the onion and ½ teaspoon of salt. Cook for 6–8 minutes, until the onions are softened and translucent.
2. Add the garlic, red pepper flakes, and nutmeg and cook for 2 minutes, until the garlic is fragrant.
3. Sprinkle the flour into the pan and mix well to incorporate it into the butter and remove any clumps. Cook for 2–3 minutes, until the flour is cooked and beginning to turn light brown in color.
4. Pour in the vegetable stock and heavy cream and stir well to combine. Bring to a simmer and cook for 2–3 minutes, until slightly thickened. Stir in the Parmesan cheese and the remaining ½ teaspoon of salt and cook the cheese until it melts, stirring continuously, about 2 minutes.
5. Stir in the lemon juice and spinach. Remove the pan from the heat.
6. Using a fine-mesh sieve, strain each egg to remove the outer egg white, the thinner layer of the egg white that tends to spread when an egg is cracked into a pan. Add each egg to its own small bowl.
7. Using a ¼ cup (30 g) measure, create 4 divots in the spinach mixture and carefully pour a strained egg into each space. Sprinkle each egg with the pepper and a pinch of Parmesan.
8. Return the pan to medium heat and cover. Cook for 5 minutes, until the egg whites are starting to set.
9. Meanwhile, turn the broiler to high. Remove the lid from the pan and broil for 2-3 minutes to cook off any excess moisture that may have accumulated and to brown the cheese.
10. Remove the pan from the oven and let cool for 10 minutes before serving with toast.