Creamy Cauliflower Gratin

A spoon filled with cauliflower gratin is being raised over a baking dish filled with the same.

Course: Side Dish

Cuisine: American / French

Keyword: holiday side dish recipe, how to cook cauliflower

Prep Time: 20

Cook Time: 40

Resting time: 10

Total Time: 1 10

Servings: people

Calories: 440kcal

Author: Kris Longwell

This gratin really is over-the-top good. We recommend fresh cauliflower. You'll need either 2 large heads or 3 small/medium heads, about 12 cups after you cut them into medium-sized florets. If using frozen, you'll need 2 lbs, thawed. The recipe can easily be halved. Perfect for a holiday feast side dish!

Print Recipe

Equipment

9"x13" dish

Ingredients

12 cups cauliflower cut into medium florets (usually, about 3 small/med heads or 2 large)
5 tbsp unsalted butter divided, plus more for greasing the dish
1 medium onion roughly chopped
1 tbsp thyme fresh, chopped
3 tbsp all-purpose flour
3 cups whole milk
2 cups heavy cream
3 tsp Kosher salt
1 tsp black pepper
1 tbsp lemon juice from 1 lemon
2 cups Gruyère cheese grated. divided
1½ cups panko Japanese bread crumbs

Instructions

Preheat the oven to 375°F and bring a large pot of water to a boil.
Butter a 9x13 baking dish.
Carefully add the cut cauliflower to the boiling water. Stir it around with a wooden spoon. Simmer for just 5 minutes then immediately drain. Set aside.
12 cups cauliflower
Melt 2 tbsp of the butter in a large saucepan, then add the onion and cook slowly over low heat until soft, 4 to 5 minutes.
5 tbsp unsalted butter, 1 medium onion
Add the thyme and then stir in the flour. Cook, stirring often, for 2 minutes.
1 tbsp thyme, 3 tbsp all-purpose flour
Slowly add the milk and cream, and whisk until all lumps are gone. Stir with a wooden spoon until thickened, about 5 to 15 minutes (heat the milk and cream before adding to expedite this process). The bechamel sauce should be slightly thicker than the consistency of gravy.
3 cups whole milk, 2 cups heavy cream
Stir in the salt, pepper, and lemon juice. Next, add 1 cup of the cheese and stir until melted.
3 tsp Kosher salt, 1 tsp black pepper, 1 tbsp lemon juice, 2 cups Gruyère cheese
Transfer the cauliflower to the prepared dish and pour the sauce over the top.
Melt the remaining 2 tbsp butter and combine with the bread crumbs and remaining cup of cheese in a medium bowl.
1½ cups panko
Top the cauliflower mixture with the breadcrumb mixture.
Bake, uncovered, for 30 to 45 minutes, until bubbly and golden on top.
Let rest for at least 10 minutes before serving.

Notes

See the video near the top of the blog post for visual guidance. If you liked the video, please subscribe to our YouTube channel.

We recommend using fresh cauliflower but take care when cutting away the core and then cutting it into bite-sized florets. Always cut AWAY from the hand that is holding the cauliflower. Take your time. If using frozen, you'll need 2 lbs, thawed, or steamed.

Be sure to not allow the cauliflower to simmer for too long. 5 minutes is plenty of time, otherwise, it will get too soft and will be mushy and retain liquid that will release during the baking. For al denté cauliflower, skip simmering completely.

The recipe can easily be halved if not serving a small gathering.

Leftovers will keep in the fridge for up to 5 days and can be frozen (baked, or unbaked) for up to 2 months. Let thaw and then heat in a 375°F until bubbly and heated through. You may need to cover the dish with foil.

Nutrition