Spinach gratin built on slow cooked onions, a nutmeg cream sauce and three pounds of squeezed spinach, baked under Parmesan and Gruyere. It goes into a hot oven at 425F for twenty minutes. An easy make ahead Christmas dinner side dish that feeds eight out of one baking dish.
Three pounds of defrosted frozen spinach holds about two cups of water. Wring it out in a clean towel, a handful at a time, until nothing more runs, or the gratin bakes into soup under the cheese.
The list calls for a tablespoon of kosher salt, then the method says season to taste, which are two different instructions. A cup and a half of Parmesan and Gruyere is already salty, so taste the sauce before the full tablespoon goes in.
Spinach Gratin
Course: Side DishCuisine: AmericanDifficulty: Easy4
servings30
minutes40
minutes300
kcalYellow onions cooked down slow, thickened with flour and nutmeg, then let down with cream and milk and packed with wrung out spinach. Finished under Parmesan and Gruyere in a hot oven.
Ingredients
4 tablespoons (1/2 stick) unsalted butter
4 cups chopped yellow onions (2 large)
1/4 cup flour
1/4 teaspoon grated nutmeg
1 cup heavy cream
2 cups milk
3 pounds frozen chopped spinach, defrosted (five 10-ounce packages)
1 cup freshly grated Parmesan cheese
1 tablespoon kosher salt, or to taste
1/2 teaspoon freshly ground black pepper
1/2 cup grated Gruyere cheese
Directions
- Heat the oven: Heat the oven to 425F.
- Soften the onions: Melt the butter in a heavy bottomed saute pan over medium heat, add the onions and cook about 15 minutes, until translucent.
- Make the sauce: Stir in the flour and nutmeg and cook for 2 minutes, then pour in the cream and milk and cook until it thickens.
- Add the spinach: Squeeze as much liquid as you can out of the defrosted spinach, then stir it into the sauce with 1/2 cup of the Parmesan. Taste, then season with the salt and pepper.
- Bake: Spread the mixture into a baking dish, scatter over the remaining Parmesan and the Gruyere, and bake 20 minutes until hot and bubbling. Serve hot.
FAQs
How long does spinach gratin really take?
The card says one hour thirty five total, but prep and cook only add up to fifty minutes. The missing forty five is the spinach defrosting, which nobody tells you. Move it to the fridge the night before and the gratin really is a fifty minute job.
Can I use fresh spinach instead of frozen?
You can, but you have to wilt it and squeeze it first, so you are doing the freezer’s work yourself. Fresh spinach is mostly water and collapses to a fraction of its weight, so you need a great deal of it. Frozen chopped is the practical choice for three pounds.
Can I make it ahead?
Build the whole thing up to the cheese topping, cover it and keep it in the fridge for a day. Scatter the Parmesan and Gruyere on just before it goes in, so the crust stays crisp. Add ten minutes to the bake if the dish starts out cold.
Is this the same as creamed spinach?
Close, but a gratin is finished under a cheese crust in a hot oven while creamed spinach stays on the stove. The baking is what gives you the browned top and the firmer set. If you want the stovetop version, try this creamed spinach.
What should I serve it with?
Beef, because the nutmeg and cheese were made to sit next to a salty crust. It also holds its heat well, which matters when the main needs resting time. A stuffed standing rib roast and this dish is a Christmas dinner with two pans.
