Easy Baked Cauliflower Gratin
This baked Cauliflower Gratin is an easy, cheesy, make-ahead side dish that's great for serving a crowd. A perfect recipe for the holidays!
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Servings: 7 servings
Calories: 296kcal
Ingredients
For the Filling:
- 1 large head of cauliflower trimmed and cut into florets (about 2 ½ lbs or 6-7 heaping cups)*
- 3 tablespoons butter plus more for greasing the dish
- ¼ cup all purpose flour
- 1 ½ cups reserved cooking water
- ¼ cup heavy cream
- 2 teaspoons Kosher salt plus more to taste
- freshly ground pepper to taste
- ¼ teaspoon fresh nutmeg
- 6 ounces Gruyere cheese grated (about 3 cups), divided
For the Topping:
- 3 tablespoons butter
- 1 clove garlic finely minced
- 1 ¼ cups panko breadcrumbs
- 1 teaspoon fresh thyme leaves
- salt and pepper to taste
Instructions
- Add the cauliflower to a medium pot, then add just enough room temperature water to barely cover. The goal is to use less water in order to achieve a more concentrated cauliflower flavor, so it's okay if some pieces are sticking out of the top.
- Bring the water up to a simmer, then cover and cook until the cauliflower pieces are al dente, about 2-3 minutes. Drain the cauliflower well and reserve the cooking water.
- Preheat the oven to 400 degrees F and butter the inside of a medium casserole dish.
- Melt butter in a medium sauce pan over medium heat, then whisk in the flour until it absorbs all the butter, about 1-2 minutes.
- Slowly whisk in 1 ½ cups of the reserved cauliflower cooking water (it should still be warm), then continue whisking until it comes up to a boil.
- Lower the heat, continue whisking, and cook for 2-3 minutes until thickened.
- Whisk in the heavy cream, salt and pepper, then turn off the heat.
- Stir in the nutmeg and ⅓ of the Gruyere cheese (about 1 cup) until the cheese is melted.
- Add the well-drained cauliflower to the cheese sauce and mix to combine. Taste for seasoning and adjust as needed - it will likely need a bit more salt and pepper.
- Scrape the cauliflower mixture into the buttered casserole dish, being sure to get every last bit of cheese sauce in there.
- Sprinkle with the remaining Gruyere cheese, then set aside while you make the topping.
- Melt the butter in a medium sauté pan over medium heat, then add the garlic and stir around until it starts to sizzle.
- Add the panko breadcrumbs, thyme leaves and a pinch of salt and pepper, then continue to stir around until light golden brown, about 5 minutes.
- Spread the breadcrumbs on top of the cauliflower in an even layer.
- Bake for about 20 minutes, or until the breadcrumbs have darkened a few shades and it's bubbling up around the sides.
- Allow the gratin to cool down for about 10 minutes before serving.
Notes
- *Use about 2 ½ lbs or 7 cups of frozen cauliflower.
- Be careful not to overcook the cauliflower while boiling, it should still be slightly firm or al dente. The time will depend on the size of your florets - check them every minute or so with a fork.
- It's really important that the cauliflower is drained very well and does not have a lot of extra liquid before adding to the cheese sauce or it will be watery.
- Use a deep dish pie plate or cast iron skillet in place of a casserole dish if desired.
- This cauliflower gratin can be made entirely in advance. Reheat in a 350 degree F oven covered for about 15 minutes, then remove the cover and bake for another 10-15 minutes until bubbling around the sides.
Nutrition
Calories: 296kcal | Carbohydrates: 16g | Protein: 11g | Fat: 22g | Saturated Fat: 13g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 6g | Trans Fat: 0.4g | Cholesterol: 62mg | Sodium: 1021mg | Potassium: 306mg | Fiber: 2g | Sugar: 3g | Vitamin A: 669IU | Vitamin C: 40mg | Calcium: 295mg | Iron: 1mg