This Creamy Potato and Vegetable Bake with White Sauce is an easy casserole topped with golden breadcrumbs and baked in the oven for 30 minutes!
My Easy Tomato Vegetable Lasagna also features the white sauce you’ll find in this casserole recipe.
As does my broccoli white sauce pasta. White sauce is incredibly versatile in many savory dishes.
🥦 Why You Will Love This Recipe
- Bakes in 30 minutes.
- Uses staple vegetables.
- Easy cheesy white sauce.
- Feeds the whole family.
Vegetables in white sauce are always guaranteed to be hearty and satisfying and this recipe is no exception.
It includes lightly steamed carrots, broccoli, cauliflower, peas, pumpkin, and potatoes.
The vegetables are then smothered in a quick and creamy white sauce made on the stovetop. It also has a generous serving of cheddar cheese melted through, DROOLING!
These are then assembled together in a large 9×13 baking dish, sprinkled with breadcrumbs, and baked for about 30 minutes.
🥗 Serving Suggestions
📋 Ingredient Notes & Substitutions
- White potatoes – such as russet potato or any white flesh potato with washed or brushed brown skin. Peeled or peel left on, I prefer to leave the peel on.
- Pumpkin – Butternut, Jap, or Kent pumpkin can be used. Substitute with extra potatoes.
- Carrot – can be substituted with zucchini or parsnip.
- Broccoli – substitute with more cauliflower, broccolini, or asparagus.
- Cauliflower – substitute with more broccoli, brussels sprout, or cabbage.
- Frozen petite peas – or larger garden peas or chopped snap peas.
- Unsalted butter – can use salted butter, reduce the added salt when seasoning if needed. Use dairy-free block cooking butter for a dairy-free veggie bake.
- All-purpose flour – substitute with gluten-free all-purpose flour if desired.
- Whole milk – make a dairy-free casserole by using dairy-free milk such as almond or soy milk.
- Ground nutmeg – can be substituted with garlic powder or left out of the recipe, just season with extra salt and pepper.
- Salt & pepper – fine sea salt, Kosher salt, and cracked black pepper work best.
- Frozen shredded cheddar cheese – or freshly grated/shredded cheddar cheese of choice.
- Breadcrumbs – use plain/regular store-bought breadcrumbs or Panko breadcrumbs for a crunchier topping. Use gluten-free breadcrumbs for a gluten-free vegetable bake.
🔪 Step By Step Instructions (with photos)
There is a full and detailed recipe card at the bottom of this post.
Step one: Prepare a large steamer with the pot half filled with water and bring it to a boil over high heat on the stovetop.
Step two: Place chopped potato, pumpkin, and carrot into the steamer and steam, covered, for 10-12 minutes until fork tender, mixing it halfway through. Transfer to a large clean bowl and set aside.
Step three: Steam broccoli florets, cauliflower florets, and thawed peas, covered, for 8-10 minutes until fork tender, mixing halfway through. Transfer into the same bowl as the other veggies and set aside.
Step four: In a large frying pan or pot add butter and melt over low heat. Whisk through the flour.
Step five: Increase heat to medium-high and once gently simmering, cook for 1 minute, while whisking.
Step six: Pour milk in a slow steady stream while whisking over medium heat. Continue to cook and whisk over medium heat until it thickens, do not let it boil or simmer, it will thicken before it reaches a bubble.
Step seven: Once thickened, reduce heat to low and whisk through ground nutmeg, and season with salt and pepper to taste.
Step eight: Whisk through thawed shredded cheese until melted over low-medium heat.
Step nine: Continue to whisk over low-medium heat until thick and smooth. Turn off heat and set it aside.
Step ten: Spoon half of the steamed vegetable mixture into the base of the greased baking dish and pour over half of the white sauce, spreading out evenly with a rubber spatula or spoon.
Step eleven: Spoon over remaining vegetables then cover evenly with the remaining sauce.
Step twelve: Sprinkle over breadcrumbs and bake for 30-35 minutes until golden on top and sizzling around the edges.
Step thirteen: Remove from oven and let stand for 10 minutes before serving. Enjoy!
💭 Tips For Recipe Success
- Chop the potato, carrot, and pumpkin into smaller chunks so they cook faster in the steamer.
- Steam the vegetables only for 10-12 minutes until they’re just fork tender.
- Don’t let the white sauce come to a boil or simmer, cook it slowly on low-medium heat until it starts to thicken.
- When the white sauce is finished, don’t let it sit for long before assembling your casserole, as it will develop a skin on top due to the milk. If this does happen, give it a whisk until it’s smooth again.
⏲️ Storage Instructions
Store leftovers in sealed containers, in the refrigerator for up to 3 days.
Re-heat leftovers in a baking dish and bake at 180ºC (356ºF) for 20-30 minutes or until heated through. Cover it with foil if it browns too fast and continue to bake until heated.
Freeze leftovers in freezer-friendly sealed containers, in the freezer for up to 2-3 months.
Reheat from frozen by thawing in the refrigerator overnight, and cooking in a preheated oven at 180ºC (356ºF) for 20-30 minutes or until heated through. Alternatively, thaw at room temperature for several hours until partially frozen or defrosted, then re-heat using the exact instructions above, with an additional 5-10 minutes if needed.
💬 Recipe FAQ’s
Yes! Easily substitute any of the vegetables with what you have on hand. I have a few suggestions above in the post under the ingredient notes. Such as parsnips instead of carrots, more potatoes instead of pumpkin, and broccolini or asparagus instead of broccoli.
Yes! Simply use 6 cups of mixed frozen vegetables instead of the individual veggies but still include the potatoes. If you don’t have potatoes or prefer to leave them out, add another 2 cups of frozen veggies, making that 10 cups in total.
Absolutely! Swap the butter for an unsalted block of dairy-free cooking butter and substitute the whole milk with a dairy-free milk such as almond milk or soy milk.
You bet! In the white sauce, use a gluten-free all-purpose flour instead of the the regular AP flour and substitute the regular breadcrumbs with gluten-free store-bought breadcrumbs.
If you enjoy this recipe, please consider leaving a ⭐️ star rating and a comment review below. I love to hear what you think and it’s much appreciated. Thank you! Your email address will not be published. Sam x
Creamy Potato and Vegetable Bake in White Sauce
- 2 cups broccoli florets
- 2 cups cauliflower florets
- 2 cups sliced carrots, approx. 2 large carrots
- 1 cup peeled and cubed pumpkin, Butternut, Jap, or Kent
- 1 cup frozen petite/baby peas, thawed
- 2 cups cubed russet potatoes, skin on or off, approx. 3 medium potatoes
- 135 g unsalted butter
- 10 Tbsp all-purpose flour
- 4 cups whole milk
- 1/2 tsp ground nutmeg
- Salt & pepper, to taste
- 2 cups frozen shredded cheddar cheese, thawed
- 3 Tbsp store-bought regular breadcrumbs, or Panko or gluten-free
- Preheat oven to 200ºC (400ºF). Liberally grease with butter or cooking spray a large 9×13 baking dish.
- Measure out the frozen peas and frozen shredded cheese and set them aside to thaw.
- Prepare a large steamer with the pot half filled with water and bring it to a boil over high heat on the stovetop.
- Place chopped potato, pumpkin, and carrot into the steamer and steam, covered, for 10-12 minutes until fork tender, mixing it halfway through.
- Transfer to a large clean bowl and set aside.
- Back in the steamer, add broccoli florets, cauliflower florets, and thawed peas. Steam, covered, for 8-10 minutes until fork tender, mixing halfway through.
- Turn off heat and transfer into the same bowl as the potato, pumpkin, and carrots.
- In a large frying pan or pot, add butter and melt over low heat.
- Once melted, increase heat to medium-high, add flour and whisk through the butter, once gently simmering, cook for 1 minute, while whisking.
- Pour milk in a slow steady stream while whisking over medium heat.
- Continue to cook and whisk over medium heat until it thickens, do not let it boil or simmer, it will thicken before it reaches a bubble.
- Once thickened, reduce heat to low.
- Whisk through ground nutmeg, and season with salt and pepper to taste.
- Add thawed shredded cheese and whisk until melted over low-medium heat.
- Turn off heat and set it aside.
- Spoon half of the steamed vegetable mixture into the base of the greased baking dish.
- Pour over half of the white sauce, spreading out evenly with a rubber spatula or spoon.
- Spoon over remaining vegetables.
- Pour over remaining white sauce, covering the vegetables evenly.
- Sprinkle over breadcrumbs.
- Bake for 30-35 minutes until golden on top and sizzling around the edges.
- Remove from oven and let stand for 10 minutes before serving.
First published in November 2018, this recipe was updated in November 2023 to include new step-by-step images, expert recommendations, storage guidelines and more.