1 tablespoon unsalted butter
1/4 cup finely chopped onion
1 pound spinach, large stems removed, coarsely chopped
1/3 cup heavy cream
1 clove garlic, minced
1/4 teaspoon grated nutmeg, preferably fresh
1/4 teaspoon kosher salt
Freshly ground black pepper
1/3 cup coarsely chopped fresh dill
Melt the butter in a large pot over medium heat. Add the onion and cook, stirring often, until soft and translucent, 3 to 5 minutes. Add the spinach, cover, and cook, stirring once or twice, until wilted, 2 to 3 minutes. Using a slotted spoon, transfer the spinach and onions to a bowl. Pour off and discard any liquid left in the pot.
Return the pot to medium heat and add the cream, garlic, and nutmeg. Let the cream come to a low simmer, and cook, stirring often, until it thickens and reduces slightly, 2 to 3 minutes. Stir in the salt and several grinds of pepper.
Give the spinach a squeeze to remove any excess liquid and return it to the pot, tossing to coat it in the reduced cream. Remove the pot from the heat and stir in the dill. Taste and season with more salt or pepper as needed.
Credit to: https://www.thekitchn.com/creamy-spinach-and-dill-257165