Sourdough Broccoli Casserole

Crisp-tender broccoli smothered in a delicious cheese sauce with a subtle sourdough tang – what’s not to love? This sourdough broccoli casserole is a bit like macaroni and cheese, but with broccoli instead of pasta! Creamy, cheesy and topped with crunchy sourdough breadcrumbs, it’s such a delicious way to serve broccoli and one the whole family will love.

Why You’ll Love This Recipe!

A Delicious Way To Eat Broccoli – My kids love broccoli but we tend to eat it the same old ways. Now that they’ve tried it with their favorite cheese sauce, we might never go back!

A Fantastic Side Dish – I love finding new ways to work sourdough discard into dinner, and this is such a delicious way to do it (with some broccoli thrown in for good measure!)

Easy to Make Stovetop or Baked – Blanch the broccoli until just tender and make a cheese sauce, and you’ve got an impressive dish! You could serve it as-is, although I love topping it with crunchy sourdough breadcrumbs and baking until it’s golden brown and bubbling (just like when I make sourdough mac and cheese). Either way is delicious!

Ingredients

• Broccoli  – I used the florets of two medium heads of broccoli, cut into bite-sized pieces. Use the stalks if you want to! I recommend peeling the stalks to remove the tough outer layer, and dicing them into small pieces so they cook in a similar time to the florets.
• Butter – I always use salted butter, but you can use unsalted too. You’ll use some for the cheese sauce and some for the breadcrumb topping.
• Sourdough Discard  –  You can use discard or active starter here, either one is fine. If your discard is old and sour it will overpower the flavor of this dish, so I recommend active starter or discard that’s only a few days old.
• Whole Milk  – I recommend whole milk, but 2% will work too.
• Chicken Broth or Stock  – I like a slightly lighter sauce paired with the broccoli, but you could use more milk instead if you prefer.
• Cheddar and Parmesan Cheese – This combination makes a smooth cheese sauce that pairs perfectly with the broccoli, plus a bit of Parmesan for the crunchy breadcrumb topping. Whenever possible, I grate the cheese myself as it makes for the smoothest, most flavorful sauce without any additives.
• Salt
• Garlic Powder – Gives a lovely mellow flavor that goes so well with the broccoli.
• Sourdough Breadcrumbs – I’ve used homemade sourdough bread, blitzed to crumbs in the food processor, but store-bought breadcrumbs are great too (I recommend panko).

How To Make A Sourdough Broccoli Casserole

Sourdough broccoli casserole is so simple to make. Instead of making a traditional roux with flour and butter, you’re using your sourdough discard to make the cheese sauce! Not only is it really easy, but it adds a subtle sourdough tang to the cheese sauce.

First you’re going to blanch the broccoli, which gives a nice crisp-tender texture and ensures the broccoli is well-seasoned. Bring a large pot of salted water to a boil. Add the broccoli florets and cook for 2 to 3 minutes, until bright green. Don’t overcook them at this point, they’ll have plenty of time to soften more in the oven. Drain immediately and set aside.

Now add butter, sourdough starter and a dash of the milk into a saucepan and whisk over low heat to form a roux. As it comes together and starts to cook, add a little more milk and continue whisking.

Once it thickens, you can turn up the heat a bit as you add more of the milk, a little at a time, until all of the milk has been added. Cook, whisking frequently, for around 5 minutes and you’ll see the white sauce begin to thicken. Slowly drizzle in the stock and continue whisking until the stock is fully incorporated.

Cook until the sauce is quite thick and coats the back of a spoon. Remove the sauce from the heat and add the shredded cheeses and garlic powder. Continue whisking until all of the cheese has melted through (it really doesn’t take long).

Add the cooked broccoli on top of the cheese sauce and stir to coat thoroughly, then transfer the broccoli and cheese mixture into a 2-quart baking dish. At this point it’s delicious broccoli in cheese sauce, so you could eat it like this (I’ve been known to sneak many a bite at this stage!).

The Parmesan-breadcrumb topping takes it to the next level though! To make the topping, combine the breadcrumbs, Parmesan cheese, and melted butter in a small bowl. Stir to combine and sprinkle on top of the broccoli and cheese mixture. Bake for about 25 minutes, or until the topping is golden brown and the cheese is bubbling on the edges.

What To Serve With Sourdough Broccoli Casserole

This sourdough broccoli casserole makes such a delicious side dish for a family dinner, but it’s also great on a holiday table! If you’re serving it for Thanksgiving, pair it with my sourdough green bean casserole, some creamy sourdough au gratin potatoes and a batch of sourdough dinner rolls for soaking up all that delicious sourdough gravy!

How To Store + Freeze

This sourdough broccoli casserole is great for making in advance. You can prepare it up to 3 days ahead, making it a great option for Thanksgiving or anytime you want to get some of the cooking done in advance. Assemble the casserole, but don’t add the topping or bake it until right before serving.

Once baked, it lasts in the refrigerator, covered tightly in aluminum foil for around 3 to 5 days. You can reheat the leftover broccoli casserole in the microwave for ease, or gently in a moderate oven (around 180ºC/350ºF) to maintain the crunchy topping.

If you want to freeze your sourdough broccoli casserole, portion it out into smaller portions. Wrap well with as much air pressed out as possible before placing in the freezer for up to 3 months. Thaw overnight in the refrigerator before reheating in a moderate oven (around 180ºC/350ºF). Just keep in mind that the texture may be different after freezing.

Share the sourdough love!