Description
This easy baked cauliflower gratin is a classic French side dish featuring tender cauliflower florets smothered in a rich, creamy Gruyere cheese sauce, topped with a golden, garlicky panko breadcrumb crust. Perfect for holiday gatherings and make-ahead meals, this gratin blends buttery, cheesy comfort with a crispy topping for a crowd-pleasing dish.
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
- 1½ 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
- 1¼ cups panko breadcrumbs
- 1 teaspoon fresh thyme leaves
- Salt and pepper to taste
Instructions
- Cook the cauliflower: Add the cauliflower florets to a medium pot and cover with just enough room temperature water to barely submerge them. Bring to a simmer, cover, and cook until the cauliflower is al dente, about 2-3 minutes. Drain well, reserving the cooking water.
- Preheat oven and prepare dish: Preheat your oven to 400°F (205°C). Butter the inside of a medium casserole dish to prevent sticking.
- Make the roux: In a medium saucepan over medium heat, melt 3 tablespoons of butter. Whisk in the flour and cook until it absorbs the butter and slightly toasts, about 1-2 minutes.
- Add cooking water and thicken sauce: Slowly whisk in 1½ cups of the reserved cauliflower cooking water (warm). Bring to a boil, then reduce heat and whisk continuously until the sauce thickens, about 2-3 minutes.
- Finish cheese sauce: Whisk in the heavy cream, 2 teaspoons salt, freshly ground pepper, and nutmeg. Turn off heat and stir in one-third of the grated Gruyere cheese (about 1 cup) until melted and smooth.
- Combine cauliflower and sauce: Add the drained cauliflower to the cheese sauce, mixing gently to coat evenly. Taste and adjust seasoning with additional salt and pepper if needed.
- Assemble gratin base: Transfer the cauliflower mixture into the buttered casserole dish, scraping to include all the cheese sauce. Sprinkle the remaining Gruyere cheese evenly over the top.
- Prepare breadcrumb topping: In a medium sauté pan, melt 3 tablespoons butter over medium heat. Add minced garlic and cook until fragrant and sizzling. Stir in panko breadcrumbs, fresh thyme leaves, and a pinch of salt and pepper. Continue cooking and stirring until the breadcrumbs are golden brown, about 5 minutes.
- Top and bake: Evenly spread the golden breadcrumb mixture over the cauliflower. Bake in the preheated oven for about 20 minutes, or until the topping is browned and the gratin is bubbling around the edges.
- Rest and serve: Remove from oven and let the gratin cool for about 10 minutes before serving to set and enhance flavors.
Notes
- Use freshly grated Gruyere cheese for the best melting quality and flavor.
- Reserve the cauliflower cooking water carefully as it adds essential flavor and thickening power to the sauce.
- This dish can be prepared ahead and baked just before serving.
- Panko breadcrumbs can be substituted with regular breadcrumbs, but panko adds a lighter, crispier texture.
- Adjust seasoning to your taste, especially salt and pepper, before baking.
- Allow the gratin to rest after baking to avoid burns and help the sauce set.
