Easy Broccoli Gratin With Rich Creamy Cheese Sauce
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Tender broccoli florets baked in a rich, creamy cheese sauce until golden and bubbling. This easy broccoli au gratin is the side dish that disappears first every single time.
Easy Broccoli Gratin
Broccoli Gratin is a delicious, cheesy casserole made with tender, heartwarming broccoli and a creamy bechamel sauce, baked to perfection.
This gratin makes a great alternative to other oven-baked dishes. It combines fresh or frozen broccoli with a creamy cheese sauce, then covers it with cheese and bakes it in the oven in less than twenty minutes.

This broccoli recipe is perfect when you are short on time and only need a few ingredients to have it ready from oven to plate.
Why You Will Love This Cheesy Broccoli Casserole
- Simple yet versatile: It can serve as a filling vegetarian main dish or a side for meat lovers. The ingredients are simple and are usually items that you already have on hand in your kitchen. You can choose the type of cheese you use, and if you don’t have fresh broccoli available, no problem! Just use frozen broccoli after thawing. The best thing about this recipe is that you can substitute the broccoli for any other vegetable, such as cauliflower or potatoes. The flavors in this easy method will make this casserole taste amazing, no matter what you add as the main ingredient.
- Quick and Easy: If you need a speedy dinner option, broccoli baked in a creamy cheese sauce is the way to go. It will be ready from oven to table in less than twenty minutes. With minimal ingredients, this is a no-fuss dish.
- Cost-effective: Affordable and readily available ingredients make this a perfect meal to whip up quickly.
Ingredients needed for this Broccoli Casserole Recipe
- Broccoli: This cruciferous vegetable makes an excellent choice for dinner. Fresh broccoli florets are the obvious choice, but frozen broccoli florets are just as good. Just remember to thaw it before cooking.
- Lemon: Adding lemon juice during boiling can brighten the broccoli’s color and enhance its flavor.
- Cooking oil: Any mild-flavored cooking oil, such as sunflower or canola/ vegetable oil, will do the trick. You can also make it with butter.
- All-purpose flour: Also known as plain flour in some countries, such as the UK, this flour doesn’t contain any raising agents. However, it will do a fine job of thickening the sauce as it cooks, helping it reach a creamy consistency.
- Milk: Full-fat milk will give this broccoli gratin a rich and creamy texture, but you can also use reduced-fat milk or even plant-based alternatives, such as soy, oat, almond, or coconut milk. Keep in mind that these milks may bring different flavors to the dish.
- Mature Cheddar Cheese: To make the cheesy sauce that coats the broccoli and gives the dish a beautifully browned, bubbly golden topping, shredded cheddar cheese is the best choice for this recipe, as it packs a lot of flavor.
- Salt: Add salt to taste to the sauce before pouring it over the broccoli. If you prefer, you can sprinkle some evenly over the cooked broccoli instead.

Equipment Needed for Broccoli Gratin
- Kitchen knife: It is essential to have a high-quality, sharp knife, as a dull one can cause more accidents!
- Saucepan: A small- to medium-sized saucepan is ideal for this recipe.
- Strainer/Sieve: Useful for effortlessly straining water from the pan. A nice big one will prevent your cooked produce from falling out.
- Hand whisk: A whisk works better than a wooden spoon for making white sauce because it prevents lumps and creates a smooth texture by seamlessly mixing the milk into the flour-and-oil base.
- Casserole dish or baking dish of choice: A slightly deep, rectangular, or round dish is the ideal bakeware for this gratin recipe.
- Oven: Preheating your oven while preparing the rest of your dish will save time during cooking. If it has a timer, you can set it to turn off as soon as it reaches the desired temperature.
How to Make Broccoli Au Gratin Simply
If you are using frozen florets, make sure to give them time to thaw, as this will speed up cooking time in the long run.
Once the broccoli is cut and washed, bring some water to a boil, add the broccoli to the boiling water with a squeeze of lemon, and cook for approximately 3 minutes. The broccoli will be tender with a slight crunch. Try not to overcook the broccoli.
There are only a few steps to make this delicious, simple broccoli au gratin recipe. Firstly, chop up your broccoli into small bite-sized pieces and wash them if you use fresh broccoli.
Transfer the broccoli to a baking dish once cooked, and in a separate saucepan, whisk the oil and flour together over medium heat. Once the mixture emulsifies, add the milk slowly while continuing to stir. As it gets hot and bubbles start to form, the sauce thickens.

Add over half of the shredded cheese while continuing to mix. The melted cheese will help thicken the sauce further as it continues to boil. You can now season with salt or any other seasoning of choice.
Remove from heat, slowly pour the sauce over the tender broccoli florets, and top with the remaining cheese. Bake in the preheated oven at 392°F/200 °C for about 15 minutes, or until the broccoli gratin turns golden brown. Your dish is now ready to enjoy!
Substitutions and Variations
This broccoli gratin recipe is so versatile. You can always find an alternative that will make you maintain quality and flavor.
- The main ingredients in this recipe are broccoli and cheese, but you can switch to or add other ingredients. You can use cauliflower, potatoes, leafy greens, and beans.
- The same goes for cheese; if you prefer, you can alternate with Gouda, mature Edam, Colby, and Monterey Jack cheese. These will make fantastic alternatives.
- If strong cheese is not your thing, you can always stick to the mild cheese of your choice. For a rich, creamier sauce, try adding cream cheese during cooking.
- Because this tasty recipe allows customization, the milk you use for the white cheese sauce can be any milk you prefer. The full-fat variety will make the sauce taste creamier, but other types of milk will work just as well.
- You can add more bite to your broccoli by adding panko breadcrumbs or other breadcrumbs to the grated cheese to create a crunchy topping before baking.
How to Store the Leftovers:
- To Store: Any leftovers can be stored in an airtight container in the fridge for up to 4 days.
- To Freeze: You can freeze this dish for up to three months in an airtight container. Thaw the night before, then thaw when ready to eat.
- To Reheat: Cover the dish with foil and reheat in the oven at moderate to high temperature for 10-20 minutes. Alternatively, heat gently in the microwave. Settings may vary.
What Can Go With Broccoli and Cheese Casserole
This delicious, easy gratin makes a delectable broccoli side dish for any occasion. You can pair this dish with roasted meat, grilled fish, cheesy garlic bread, or even rice or quinoa.
Simple, Easy, and Tasty Broccoli Gratin
Broccoli can be a great comfort food, and paired with its health benefits, tender texture, and wholesome flavor, it can make a great side dish or main dish, such as this heartwarming bake. With simple ingredients and an easy, straightforward recipe, this dish will soon become a delightful addition to mealtimes!
Common Questions Answered
How do you know when broccoli is ready?
Broccoli is ready once you can pierce it with a fork. Remember that if you want to keep that vibrant green color, try not to exceed 7 minutes while cooking, as the color can dull.
Can I use any cheese on top?
For the cheese sauce itself, you can vary the cheese, but if you want that golden-brown, crispy layer, a hard cheese such as Cheddar, Gouda, Edam, Gruyère, or Parmesan is best for topping. However, you are not restricted and can mix it up!

Easy Broccoli Gratin With Rich Creamy Cheese Sauce
Equipment
- Hand whisk
- Strainer
- Oven
Ingredients
- 3 cups broccoli about 1 medium head
- ½ lemon
- ½ teaspoon salt
- 3 tablespoons butter
- 3 tablespoons all-purpose flour
- 2 cups milk
- 1 cup mature cheddar cheese and extra for topping
Instructions
- Cut the broccoli into small florets, wash, and rinse.
- Boil some water in a saucepan, and put the broccoli in when the water reaches boiling point.
- Squeeze the lemon into broccoli. Cook for 3 minutes, then strain the broccoli and discard the water. Place the veg onto a small casserole dish.
- Melt the butter in another saucepan over medium heat and add the flour. Stir it using a hand whisk until you see the flour emulsified with the oil.
- Add the milk little by little while whisking. Continue cooking and stirring until the mixture thickens. You want it at heavy-cream consistency.
- Then add the grated cheese to the milk. Keep whisking and cooking until the mixture thickens and starts boiling.
- Pour the milk mixture over the broccoli and bake at 392°F/ 200°C for about 15 minutes or until your broccoli au gratin turns golden brown.
Notes
- You can use any neutral cooking oil. I use vegetable oil or sunflower oil. If you like, you can use butter instead.
- Squeezing a lemon will help keep broccoli’s color fresh and green.
- Strongly flavored mature cheddar cheese is preferred. Matured Edam, Gouda, Monterey Jack, or Colby cheese is a suitable substitute.









