Cheesy Broccoli Rice Casserole (From Scratch)

Every family has one: the dependable side dish that quietly upstages the main. Around here, it is this casserole. Creamy, cheesy, full of tender broccoli folded through fluffy rice, baked under a golden, bubbling top. It shows up at holiday tables, potlucks, and plain old Tuesday dinners with equal confidence, because it pairs with nearly everything and pleases nearly everyone, including the people who swear they do not like broccoli.

The difference in this version is the sauce. No canned soup. A simple homemade cheese sauce takes about five extra minutes at the stove, and in exchange you get real cheddar flavor, a smooth texture that never tastes tinny, and seasoning you control completely. Five minutes. Worth every one. The casserole also assembles ahead happily, which makes it a genuine gift on the days when dinner needs to already be handled.

Three Decisions That Fix This Casserole

Most mediocre versions of this dish fail in the same three places, so this recipe defends against all of them. First, the rice cooks slightly firm before it goes in, because it keeps absorbing sauce in the oven; start with soft rice and you have baked yourself a mushy casserole. Second, the broccoli gets a brief blanch instead of going in raw, so it stays bright green and tender rather than crunchy in some bites and army-green in others. Third, the cheese sauce is built on a proper roux, so it bakes up smooth instead of oily or separated, and the sharp cheddar is stirred in off the heat so it melts silky instead of grainy.

Assemble Your Ingredients

1 cup long-grain white rice (or 3 cups cooked rice)
4 cups broccoli florets, cut bite-size (about 1 large head or a 12-ounce bag)
3 tablespoons unsalted butter
1 small yellow onion, finely diced
2 garlic cloves, minced
3 tablespoons all-purpose flour
2 cups whole milk
1/2 cup low-sodium chicken or vegetable broth
1 teaspoon Dijon mustard
1/2 teaspoon garlic powder
1/2 teaspoon kosher salt, plus more to taste
1/4 teaspoon black pepper
2 1/2 cups shredded sharp cheddar cheese, divided
1/2 cup crushed buttery crackers or panko breadcrumbs (optional topping)
1 tablespoon melted butter, if using the topping

Building the Casserole

Heat the oven to 350°F. Grease a 9×13-inch baking dish.
Cook the rice according to the package directions, reducing the cooking time by about 2 minutes so the grains stay slightly firm. Fluff with a fork and set aside.
Bring a pot of salted water to a boil. Blanch the broccoli for 2 minutes, then drain and rinse briefly under cold water to stop the cooking. Drain very well.
In a large saucepan over medium heat, melt the butter. Cook the onion for 4 to 5 minutes until soft. Stir in the garlic for 30 seconds.
Sprinkle in the flour and whisk for 1 minute to form a smooth paste.
Slowly pour in the milk and broth, whisking constantly. Simmer for 3 to 4 minutes, whisking often, until the sauce thickens enough to coat a spoon.
Remove from the heat. Stir in the mustard, garlic powder, salt, and pepper. Add 2 cups of the cheddar a handful at a time, stirring until melted and smooth.
Fold the rice and broccoli into the sauce until everything is evenly coated. Taste and adjust seasoning.
Spread into the prepared dish. Top with the remaining 1/2 cup cheddar and, if using, the cracker crumbs tossed with melted butter.
Bake for 25 to 30 minutes, until bubbling at the edges and golden on top. Rest 10 minutes before serving so the sauce sets slightly.

Details That Keep It Creamy, Not Soupy

Shred your own cheese. Pre-shredded cheese carries anti-caking starch, and starch is how cheese sauces turn grainy. A block of sharp cheddar melts smoother and tastes like more.
Drain the broccoli like you mean it. Extra water is the main cause of a watery casserole. Let the florets sit in the colander while you build the sauce.
Season the sauce boldly. Rice and broccoli are both mild, so the sauce should taste well seasoned all on its own before anything gets folded in.
Day-old rice is a secret weapon. If you have leftover rice, use it. Firm, separate grains give the casserole an excellent texture.
Respect the rest. Ten minutes out of the oven lets the sauce thicken to a scoopable consistency instead of a puddle.

Spin-Offs Worth Trying

Make it dinner: Fold in 2 cups of diced cooked chicken or rotisserie chicken and stop calling it a side.
Ham and broccoli: A cup of diced ham turns this into a great post-holiday bake.
Cauliflower blend: Replace half the broccoli with cauliflower florets for a milder flavor.
Some heat: A pinch of cayenne in the sauce and pepper jack for half the cheese wakes it right up.
Brown rice: Works well; cook it fully first since it takes longer, and add a splash more broth to the sauce.

Make It Early, Keep It Later

Leftovers refrigerate in an airtight container for up to 4 days. Reheat portions in the microwave with a splash of milk, or warm the whole dish, covered, in a 350°F oven for about 20 minutes. The casserole also freezes well for up to 2 months; thaw overnight in the fridge before reheating. Making it ahead is easy: assemble everything except the topping, cover, and refrigerate for up to 24 hours. Add the topping and bake as directed, giving it about 5 extra minutes since it starts cold.

Good Company for a Casserole

Roast chicken, baked ham, or grilled pork chops
A crisp green salad to balance the richness
Roasted carrots or green beans, if a second vegetable sounds good
Nobody at all: it stands happily on its own as a meatless main with a salad

Casserole Questions We Hear

Can I use frozen broccoli?

Yes. Thaw it first and drain it very well, pressing gently to get the excess water out. Skip the blanching step, since frozen broccoli is already blanched before freezing.

Why is my casserole watery?

Usually the broccoli was not drained well, or the sauce was too thin going in. Make sure the sauce properly coats a spoon before you fold everything together, and let the finished casserole rest before serving.

Can I use a different cheese?

Absolutely. Gruyere, Monterey Jack, or a cheddar and mozzarella blend all melt well. Keep at least part of it sharp cheddar for the classic flavor.

Is this casserole gluten free?

It can be. Swap the flour for a 1:1 gluten free flour blend and skip the cracker topping, or use gluten free crumbs.

Ingredient-by-Ingredient Notes

Sharp cheddar: Sharp or extra-sharp is not a suggestion here. Mild cheddar disappears against the rice and broccoli, while sharp keeps its voice in the sauce. And a block you shred yourself melts noticeably smoother than bagged shreds.
Long-grain white rice: It stays distinct and fluffy through the bake. Jasmine is a fine substitute. Instant rice is not recommended; it turns soft and gummy in the sauce.
Broccoli: Fresh florets cut small and even give the best texture. Include some of the tender stem, peeled and diced. It is sweet, and it cooks at the same rate as the florets.
Whole milk: Whole milk makes a sauce that is creamy without being heavy. Two percent works with a slightly lighter result. Avoid skim, which makes the sauce thin and less stable.
Dijon mustard: A teaspoon disappears into the background and quietly sharpens the cheese flavor, a classic trick in cheese sauces. Yellow mustard is too assertive; use half as much if it is all you have.

When a Cheese Sauce Misbehaves

Grainy cheese sauce almost always traces back to heat: the sauce boiled after the cheese went in, or the cheese went in all at once into a very hot base. Off the heat, added gradually, is the rule. If it happens anyway, a splash of warm milk whisked in over the lowest heat often rescues it. An oily-looking top usually means the bake ran a little long or the cheese was very high in fat; skip the blotting, because a short rest lets the sauce reabsorb most of it. And if the casserole looks loose the moment it leaves the oven, do not panic. That ten-minute rest is part of the recipe, and the sauce sets up considerably as it cools slightly.

Can I make this in a slow cooker?

You can, though the top will not brown. Combine the sauce, rice, and broccoli as directed, cook on LOW for 2 to 3 hours until the rice is tender, then add the topping if you like and serve. It is a handy option when the oven is busy with a holiday main dish.

Fitting It Into a Holiday Oven Schedule

On holidays, oven space is the scarcest resource in the kitchen, and this casserole is a cooperative guest. Assemble it a day ahead and hold it covered in the fridge. Bake it in the morning and reheat it, covered, at 325°F while the main dish rests. Or hold it warm in a slow cooker on the buffet. If the turkey or ham is hogging the oven at a higher temperature, the casserole tolerates 375°F for about 20 minutes without complaint; just watch the topping near the end. Give it the oven slot right after the main comes out, and it will be bubbling at the exact moment everyone sits down.

Casserole Facts

Prep time: 20 minutes
Cook time: 30 minutes
Total time: 50 minutes
Servings: 8 as a side, 4 to 6 as a main
Cuisine: American
Course: Side dish or dinner