Cheesy Broccoli au Gratin

If you’re looking for a way to help your family eat more broccoli, this broccoli au gratin recipe is here to save the day! This recipe is like the green vegetable cousin to cheesy scalloped potatoes. It may go without saying, but smothering veggies with a creamy sauce, melty cheese and crispy bread crumbs is a surefire way to get kids (or anyone still learning to love vegetables) to try them.

Broccoli gratin starts with a simple flour-thickened sauce made on the stovetop. Fresh broccoli florets, a few pantry seasonings and shredded cheddar and Parmesan are mixed with the sauce and baked to bubbly perfection. It may sound indulgent, but the milk and cheeses used in gratin recipes are actually excellent sources of both protein and calcium.

What does au gratin mean?

Au gratin is a French term that refers to baked dishes with grated cheese and a browned crust, typically made from bread crumbs. This broccoli au gratin recipe is topped with panko bread crumbs and shredded Parmesan, both of which brown in the oven to create an irresistibly crispy and golden crust.

Ingredients for Broccoli Au Gratin

• Butter: Melted butter is a flavorful fat that is used to cook the aromatics and the flour to create the foundation of the cream sauce. You’ll need half a stick of either salted or unsalted butter.
• Onion and garlic: A small amount of sauteed onion and garlic adds irresistibly savory and complex flavor to this gratin.
• All-purpose flour: Flour added to the melted butter turns into a roux that thicken the cream sauce.
• Milk: You’ll need 2 cups of 2% milk to make the creamy sauce. You can substitute whole milk for a more decadent flavor.
• Broccoli: Choose a large bunch of broccoli and cut it into bite-size florets. You can save time by purchasing prepared broccoli florets, but you may need to trim larger pieces to make them uniform.
• Shredded cheese: This broccoli au gratin recipe contains sharp cheddar and Parmesan. For the best melting, grate your own cheese from the block, either by hand or with a food processor. Packaged shredded cheese is convenient, but contains anti-caking agents that can give it a powdery mouthfeel when melted.
• Seasonings: In addition to salt and pepper, our broccoli gratin is seasoned with ground mustard to balance the richness of the dairy, and with a touch of cayenne pepper for subtle heat.
• Bread crumbs: To make this an authentic au gratin recipe, we make a crispy topping by sprinkling panko bread crumbs mixed with shredded Parmesan on top of the casserole during the last ten minutes of baking.

Directions

Step 1: Saute the aromatics

Preheat the oven to 375°F. In a large saucepan, melt the butter over medium heat. Add the chopped onion and cook it until it’s tender, four to five minutes. Add the minced garlic and cook for one minute longer.

Step 2: Make the sauce

Stir in the flour and cook until it’s browned, one to two minutes. Gradually whisk in the milk. Bring the sauce to a simmer and cook until it has thickened, two to three minutes.

Editor’s Tip: We’re making a white roux to thicken the broccoli gratin sauce. The flour only needs to be cooked for a few minutes to remove the taste of raw flour. Add the milk when the flour mixture is bubbly, foamy and looks like a thick paste.

Step 3: Add the broccoli and cheese

Remove the saucepan from the heat. Stir in the broccoli, cheddar, 1/4 cup of the Parmesan, the salt, pepper, mustard and cayenne. Stir to combine.

Editor’s Tip: If your saucepan isn’t big enough to stir everything together, place the broccoli, cheese and seasonings in the baking dish, pour the sauce over them and then mix.

Step 4: Bake the casserole

Spoon the mixture into a greased 2-quart baking dish. Bake the casserole, uncovered, for 25 to 30 minutes.

Step 5: Add the cheesy breadcrumbs

Remove the baking dish from the oven. Sprinkle the top of the broccoli gratin with the panko and the remaining 1/4 cup of Parmesan. Return the casserole to the oven and bake until the sauce is bubbly and the topping is golden brown, another 8 to 10 minutes.

Editor’s Tip: If the top of your gratin takes a while to brown or if you want it extra crispy, pop it under the broiler for a minute or two.

JOSH RINK FOR TASTE OF HOME

Broccoli Au Gratin Variations

• Switch up the veggies: Increase your intake of nutritious cruciferous veggies by replacing half of the broccoli with cauliflower florets or halved Brussels sprouts. You could also add a cup of sliced carrots or mushrooms for even more veggies.
• Use herbs: Add finely minced herbs like parsley, thyme or rosemary to the cream sauce for even more flavor.
• Use different cheese: You can substitute any melting cheese for the sharp cheddar or Parmesan in this recipe. Experiment with shredded Gruyere, fontina or mozzarella for a more complex and cheesy flavor.
• Change the topping: Try topping the casserole with seasoned bread crumbs, crushed buttery round crackers or even slivered almonds for extra crunch.

How to Store Broccoli Au Gratin

Allow the broccoli au gratin to cool to room temperature, then transfer it to an airtight storage container. Store it in the refrigerator for up to four days. Reheat single servings in the microwave, or bake the remaining casserole in a 350° oven for 20 to 30 minutes until it’s warmed through. Adding a splash of milk or cream to the gratin before reheating it can help loosen the sauce.

Can you make broccoli au gratin ahead of time?

Yes, you can complete most of the prep work for this broccoli au gratin recipe a full day ahead of time. Prepare the recipe as written through Step 3. Transfer the cheesy broccoli to a casserole dish, cover it tightly with storage wrap and place it in the refrigerator up to one day in advance. When you’re ready to bake it, remove the dish from the fridge while the oven preheats, then cook as directed.

Can you freeze this au gratin broccoli recipe?

Technically you can freeze broccoli au gratin, but doing so may alter the sauce’s texture. We don’t recommend freezing casseroles with lots of dairy ingredients, since dairy tends to separate when frozen and thawed. This will result in a watery dish.

Broccoli Au Gratin Tips

JOSH RINK FOR TASTE OF HOME

What is the difference between broccoli au gratin and broccoli casserole?

Both dishes feature broccoli baked with a creamy sauce, but the ingredients in broccoli au gratin and broccoli casserole can differ. Broccoli au gratin typically features a roux-thickened cream sauce with melted cheese and a crispy bread crumb topping. Broccoli casserole recipes may contain condensed cream soup, mayonnaise, sour cream or other creamy ingredients, and may or may not contain cheese.

Is it better to use fresh or frozen broccoli in this gratin recipe?

You can use fresh or frozen broccoli florets to make broccoli au gratin. Store-bought frozen broccoli is a time-saver since you don’t have to chop the florets. However, you do have to thaw the frozen broccoli before assembling the casserole. Drain the thawed broccoli well to prevent excess liquid from making your gratin watery.

What to serve with broccoli au gratin?

Broccoli au gratin is an excellent side dish for hearty protein mains, such as roasted pork tenderloin, roast chicken or even meatloaf. If you’re in the mood for a meatless meal, serve the baked broccoli with a side salad and crusty bread for mopping up every last bit of sauce.