Cauliflower au Gratin

Ingredients

• 1 head, about 1.36 kg (3 lb)cauliflower, cut into large florets
• 2garlic cloves, minced
• 57 g (4 tablespoons; ½ stick)unsalted butter
• 16 g (2 tablespoons)arrowroot starch
• 475 ml (2 cups)hot milk
• About 100 g (1 cup)freshly grated Gruyère or Swiss cheese
• 1 teaspoonsalt
• ½ teaspoonfreshly ground black pepper
• ¼ teaspoonground nutmeg
• 227 g (8 oz), cooked and choppedbacon (optional)
• About 25 g (¼ cup)freshly grated Parmesan and Gruyère or Swiss cheese
• About 30 g (¼ cup)Italian breadcrumbs, regular or gluten-free
• 28 g (2 tablespoons), meltedbutter

Instructions

1. 1

   Preheat the oven

   Heat the oven to 190°C (375°F).

2. 2

   Boil the cauliflower

   Bring a large pot of water to the boil. Carefully add the cauliflower florets and cook for about 5 minutes, until just tender but still firm. Drain well in a colander and transfer to a 2-litre casserole dish.

3. 3

   Make the cheese sauce

   Melt the butter in a medium saucepan over medium heat. Stir in the arrowroot starch and cook for about 1 minute, until thickened. Gradually whisk in the hot milk, then add the cheese, salt, pepper and nutmeg. Whisk until the cheese has melted and the sauce has thickened. Pour the sauce evenly over the cauliflower, then scatter the cooked bacon over it if using.

4. 4

   Add the topping

   Top with the Parmesan and cheese. Mix the breadcrumbs with the melted butter and scatter over the dish. Bake at 190°C (375°F) for 20–25 minutes, until bubbling and lightly browned on top.

What is cauliflower au gratin?

Au gratin describes a dish baked with a browned topping, often made with cheese or breadcrumbs. This American-style side pairs cauliflower with a creamy cheese sauce and a crisp finish.

The recipe works because the florets are briefly boiled before baking, so they turn tender without needing a long time in the oven. Gruyère or Swiss cheese gives the sauce its savoury, rich character.

Nutrition and macros by portion

The nutrition label shows one serving as written: 371 calories, 20g protein, 12g carbs, 28g fat.

The cauliflower contributes most of the carbohydrates, while the milk and cheese add protein; butter, cheese and optional bacon supply much of the fat. Pair a serving with lean protein and a fresh or simply cooked vegetable for a balanced plate.

Prepare the cauliflower

Floret size: Cut the cauliflower into large, fairly even pieces so they cook at a similar rate during the brief boil.

Drain well: Excess water clinging to the florets can thin the sauce, so let them drain thoroughly before arranging them in the casserole dish.

Build a smooth sauce

Arrowroot base: Cook the starch with the melted butter for about a minute before adding the milk. Whisking in the hot milk gradually helps keep the sauce smooth.

Cheese and seasoning: Stir in the cheese, salt, pepper and nutmeg, whisking until the cheese melts and the sauce thickens. Keep whisking so the sauce is evenly combined.

Get the topping right

Cheese layer: The grated Parmesan and Gruyère or Swiss add a savoury finish over the sauce. Sprinkle it across the cauliflower before adding the crumbs.

Buttered crumbs: Mix the breadcrumbs with melted butter first, then distribute them over the top for a more even golden finish.

Check for doneness

Before baking: The cauliflower should be just tender but still firm after about 5 minutes in boiling water; it will continue cooking in the oven.

After baking: Look for bubbling sauce and a lightly browned top after 20–25 minutes at 190°C. If the top is pale, give it a little more time while keeping an eye on it.

Make it part of a meal

This rich side works well alongside roast chicken, turkey or another simply cooked main. A crisp green salad or steamed green vegetables can bring freshness to the plate.

For a holiday meal, prepare the rest of the menu with the casserole's oven time in mind. Serve it soon after baking, while the topping is still crisp.

Recipe notes & tips

• Cut the florets to a similar size so they cook evenly.
• Drain the boiled cauliflower thoroughly before putting it in the casserole dish.
• Whisk the hot milk in gradually to help keep the sauce smooth.
• Grate the cheese fresh so it melts readily into the sauce.
• Use the optional bacon for a saltier, meatier finish.
• Watch for bubbling sauce and a lightly browned top as the doneness cues.

Variations

• Use Swiss cheese: Choose it in place of Gruyère for a slightly different cheese flavour.
• Leave out the bacon: Keep the topping meat-free by omitting the optional bacon.
• Choose gluten-free crumbs: Use gluten-free Italian breadcrumbs for the topping.
• Change the crumb topping: Use only the specified Parmesan and Gruyère or Swiss instead of breadcrumbs.
• Add nutmeg carefully: Keep the measured amount for a gentle warm note in the sauce.

Common mistakes to avoid

• Overboiling the florets: Cook for about 5 minutes, stopping while they are still firm.
• Leaving water on the cauliflower: Drain it well so excess water does not loosen the sauce.
• Adding milk too quickly: Whisk it in gradually to help avoid a lumpy sauce.
• Skipping the starch cook: Give the arrowroot about a minute in the butter before adding milk.
• Uneven topping: Spread the buttered crumbs across the dish rather than leaving them in one area.
• Baking by time alone: Check for bubbling and a lightly browned top within the 20–25-minute bake.

How to store

Refrigerate leftovers in a covered container and eat within 3 days. Reheat in an oven until hot throughout; the breadcrumb topping may soften after storage.

Frequently asked questions