Cheesy Broccoli Potato Bake
A warming, creamy casserole combining tender potatoes and broccoli in a rich cheddar sauce, topped with crispy breadcrumbs. Perfect as a side dish for roasted meats or as a hearty vegetarian main course.
- Prep
- 25 min
- Cook
- 35 min
- Wait
- 10 min
- Total
- 1 hr 10 min
- Makes
- One 9×13-inch (23×33 cm) casserole, 6 servings
Steps
Before you start
- Preheat your oven to 375°F (190°C)
- Gather all ingredients and equipment
- Cut potatoes and broccoli into uniform pieces so they cook evenly
- Butter or spray the 9×13-inch casserole dish
Boil potatoes and broccoli
- In a large pot, bring 3 quarts of salted water to a rolling boil over high heat.
- Add the potato cubes and cook for 6 minutes until they start to soften but are still firm.
- Add the broccoli florets and continue cooking for 3 more minutes.
- The vegetables should be just tender but not falling apart.
- Drain in a colander and set aside.
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Ready when: Potatoes are fork-tender but still hold their shape; broccoli is bright green and tender-crisp
Tip: Do not overcook—the vegetables will finish cooking in the oven and will turn mushy if overdone now
Make cheese sauce
- In a large saucepan, melt 2 tablespoons of butter over medium heat.
- Whisk in the flour and cook, stirring constantly, for 1 minute until it forms a smooth paste (roux).
- Gradually pour in the milk and cream, whisking continuously to avoid lumps.
- Continue whisking for 3–4 minutes until the sauce thickens enough to coat the back of a spoon.
- Remove from heat and whisk in the Dijon mustard.
- Add the grated cheddar cheese and stir until completely melted and smooth.
- Season with ¾ teaspoon salt and ½ teaspoon black pepper, tasting and adjusting as needed.
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Ready when: Sauce coats the back of a spoon; cheese is fully melted and sauce is smooth
Tip: Add milk slowly and whisk constantly to prevent lumps. If lumps do form, strain the sauce through a fine-mesh sieve
Combine vegetables and sauce
- Pour the drained potatoes and broccoli into a buttered 9×13-inch baking dish.
- Pour the warm cheese sauce over the vegetables and gently fold together with a wooden spoon until all vegetables are evenly coated.
- Spread into an even layer.
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Ready when: Vegetables are evenly distributed and coated with sauce
Tip: Fold gently to keep the vegetables intact and prevent them from breaking into smaller pieces
Make breadcrumb topping
- In a small bowl, combine the panko breadcrumbs with the remaining 1 tablespoon of melted butter, garlic powder (if using), and smoked paprika (if using).
- Toss until the breadcrumbs are evenly moistened and coated with butter.
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Ready when: Breadcrumbs are evenly coated with butter
Tip: Melt the butter fresh if it has cooled; warm butter coats the crumbs more evenly
Top and bakeOven 375°F / 190°C
- Sprinkle the buttered breadcrumb mixture evenly over the top of the casserole.
- Bake in a preheated 375°F (190°C) oven for 30–35 minutes until the top is golden brown and the sauce around the edges bubbles gently.
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Ready when: Breadcrumb topping is deep golden brown; sauce bubbles around the edges
Tip: If the top browns too quickly before the edges bubble, tent loosely with foil for the last 10 minutes
Rest before serving
- Remove the baking dish from the oven and let the casserole rest at room temperature for 10 minutes.
- This allows the sauce to set slightly and makes serving easier.
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Ready when: Casserole has cooled to a comfortable serving temperature
Good to know
Tips
- Do not skip the Dijon mustard—it brightens the cheese flavor and prevents the dish from tasting one-note and heavy.
- Grate cheese fresh from a block for smoother melting; pre-shredded cheese often contains additives that prevent smooth blending.
- If your casserole dish is deeper than 2 inches, reduce the oven temperature to 350°F (175°C) and extend the baking time to 40–45 minutes to prevent the top from burning before the center heats through.
- For a lighter version, substitute Greek yogurt for half the heavy cream—the sauce will be slightly tangier but equally creamy.
Make ahead
Assemble the unbaked casserole up to 4 hours ahead. Cover with plastic wrap and refrigerate. Bake directly from the refrigerator, adding 5–10 minutes to the baking time until the top is golden and the edges bubble.
Storage & reheating
Store covered in the refrigerator for up to 3 days. Reheat covered with foil in a 350°F (175°C) oven for 15–20 minutes until warmed through. The casserole does not freeze well due to the cream-based sauce, which can separate upon thawing.
Substitutions
- sharp cheddar cheese, freshly grated → Gruyère, fontina, or a blend of sharp cheddar and gruyère. Use the same weight for equal richness and flavor. Gruyère gives a nuttier, more sophisticated taste.
- panko breadcrumbs → Crushed crackers (saltines or Ritz) or panko mixed with ¼ cup grated Parmesan cheese. Crackers add extra crunch; Parmesan adds additional savory depth.
- fresh broccoli → Cauliflower florets, green beans (cut into 1-inch pieces), or a combination of both. Use the same weight and cooking time. Cauliflower and green beans are equally tender after cooking.
- whole milk → Half-and-half (use 1 cup half-and-half and 0.5 cup heavy cream instead) or all heavy cream. Half-and-half makes the sauce richer; all heavy cream creates a very decadent dish but may overwhelm the vegetables.
