There’s something magical about gathering around the table during the holidays — the glow of twinkling lights, the comforting aroma wafting from the kitchen, and the joy of sharing a meal that feels both special and nourishing. If you’re planning a vegetarian Christmas dinner, this creamy veggie casserole deserves a spot at the heart of your celebration.
This dish is the ultimate comfort food: rich, velvety, and layered with tender vegetables and a golden, crispy topping. It brings together the warmth of a traditional holiday bake with the lighter, wholesome touch of plant-based ingredients. Whether you’re cooking for vegetarians or simply looking to add more veggie-forward mains to your festive table, this casserole is hearty enough to satisfy everyone.
With its blend of seasonal vegetables, a savory cream sauce, and a buttery crunch on top, this dish offers the kind of cozy indulgence we crave during the winter holidays.
Ingredients Overview
The key to a memorable vegetable casserole is balance — creamy without being too heavy, flavorful without overwhelming the veggies’ natural taste. Here’s a closer look at what goes into this festive favorite:
-
Cauliflower & Broccoli: These sturdy cruciferous vegetables hold up beautifully when baked, offering a tender bite without turning mushy. Their mild, nutty flavor pairs perfectly with a creamy sauce.
-
Carrots: Sliced thinly, carrots bring subtle sweetness and vibrant color. Roasting or sautéing them slightly beforehand deepens their flavor.
-
Mushrooms: For umami depth, sliced cremini or button mushrooms work wonders. They soak up the creamy sauce and add a meaty texture to the dish.
-
Green Beans: For a crisp contrast, blanching green beans briefly before baking helps them retain color and snap.
-
Onion & Garlic: The aromatic base for any flavorful casserole. Sautéed until golden, they infuse the sauce with savory depth.
-
Heavy Cream & Whole Milk: The backbone of the luscious sauce. For a dairy-free version, full-fat coconut milk or a plant-based cream (like cashew or oat) works well.
-
Flour & Butter: Used to make a roux that thickens the cream sauce. For a gluten-free option, use a 1:1 gluten-free flour blend or cornstarch.
-
Cheddar Cheese: Sharp cheddar melts beautifully and adds richness. Gruyère or a mild smoked gouda also make lovely substitutes. For a vegan twist, go for a meltable plant-based cheese.
-
Herbs (thyme, sage, parsley): Fresh or dried herbs bring holiday flavor to life. Sage and thyme, in particular, evoke that classic Christmas aroma.
-
Breadcrumbs or Crushed Crackers: For that irresistible golden crust. Panko is extra crunchy, but you can use crushed Ritz-style crackers or even crushed nuts for a gluten-free alternative.
-
Olive Oil or Butter: Drizzled over the top for a perfectly crispy finish.
Optional Add-ins
-
Butternut Squash or Sweet Potato: For an extra hint of sweetness.
-
Leeks or Shallots: As a more delicate substitute for onions.
-
Chickpeas: Add some protein and texture if serving as a main course.
Step-by-Step Instructions
1. Preheat and Prepare
Start by preheating your oven to 375°F (190°C). Lightly grease a large baking dish with butter or olive oil. This prevents sticking and adds flavor.
2. Par-Cook the Veggies
Bring a large pot of salted water to a boil. Add the carrots, green beans, broccoli, and cauliflower, and blanch for 3–4 minutes. Drain and immediately rinse under cold water to stop the cooking. This step keeps the veggies vibrant and crisp-tender.
3. Make the Creamy Sauce
In a large skillet over medium heat, melt 2 tablespoons of butter. Add chopped onions and cook until soft and golden, about 5–6 minutes. Stir in the garlic and cook for 1 minute.
Sprinkle in 2 tablespoons of flour and stir continuously to make a roux. Cook for another 2–3 minutes until it smells slightly nutty — don’t let it brown too much.
Slowly whisk in 1 cup of whole milk and 1 cup of heavy cream, stirring until smooth. Let the sauce simmer for 4–5 minutes until thickened.
Add salt, pepper, fresh thyme, and sage. Stir in 1½ cups of shredded cheddar cheese until melted and creamy.
4. Assemble the Casserole
In a large mixing bowl, combine the par-cooked vegetables and sliced mushrooms. Pour the creamy cheese sauce over the top and gently mix until everything is well coated.
Transfer the mixture to your prepared baking dish and spread evenly.
5. Add the Topping
In a small bowl, combine 1 cup of breadcrumbs with 2 tablespoons of melted butter and a sprinkle of grated cheese. You can also add a teaspoon of chopped parsley or thyme.
Sprinkle the topping evenly over the casserole.
6. Bake
Place the dish in the oven and bake for 25–30 minutes, or until bubbling and golden on top. If the topping needs more color, broil for 2–3 minutes at the end, watching closely.
7. Rest and Serve
Let the casserole rest for 10 minutes before serving. This helps the sauce set slightly and makes for easier scooping.
Tips, Variations & Substitutions
-
Make Ahead: Assemble the casserole (without the topping) up to 1 day in advance. Store in the fridge, then add topping and bake before serving.
-
Vegan Option: Swap dairy cream with unsweetened oat or cashew cream, and use vegan cheese. Substitute the butter with olive oil or vegan margarine.
-
Gluten-Free Version: Use gluten-free flour in the roux and substitute panko with crushed GF crackers or crushed almonds.
-
Protein Boost: Add cooked lentils, chickpeas, or cubed tofu for extra substance, especially if this is your main dish.
-
Holiday Twist: Add roasted chestnuts or dried cranberries for festive flair.
-
Spice it Up: A pinch of nutmeg in the sauce adds a warm, holiday touch. Crushed red pepper flakes can provide a gentle heat.
Serving Ideas & Occasions
This creamy veggie casserole makes a beautiful centerpiece for a vegetarian Christmas dinner. Serve it with:
-
Cranberry sauce: The tartness cuts through the richness.
-
Garlic mashed potatoes: For an extra comforting side.
-
Roasted Brussels sprouts or glazed carrots: For color and crunch.
-
Warm dinner rolls or crusty sourdough: Perfect for mopping up the sauce.
-
White wine or sparkling apple cider: Both pair wonderfully with the creamy, herby flavor profile.
This dish works beautifully as part of a buffet, potluck, or formal sit-down dinner. It’s also excellent for post-holiday leftovers — just reheat and enjoy!
Nutritional & Health Notes
While rich and indulgent, this casserole offers plenty of nutritional value from its variety of vegetables. Broccoli and cauliflower are high in fiber, vitamin C, and antioxidants. Mushrooms provide selenium and B vitamins, while carrots are packed with beta-carotene.
Using a combination of milk and cream allows for customization — you can reduce the richness by substituting more milk or using plant-based options. Adding legumes like chickpeas increases the protein and fiber, making it more satisfying.
Portion control is key with creamy dishes — pair this casserole with lighter sides for a balanced plate. If you’re cooking for guests with dietary needs, this recipe adapts easily with vegan, gluten-free, and low-carb alternatives.
FAQs
Q1: Can I make this casserole ahead of time?
Yes! Assemble the casserole without the topping, cover tightly, and refrigerate for up to 24 hours. Add the topping just before baking. This makes it perfect for prepping the night before a big meal.
Q2: What vegetables work best in this casserole?
The recipe is versatile — use cauliflower, broccoli, carrots, mushrooms, green beans, or leeks. Just make sure all vegetables are par-cooked so they finish evenly in the oven.
Q3: How do I make it vegan?
Replace dairy cream with a plant-based alternative like cashew or oat cream. Use vegan butter and shredded vegan cheese. The result is just as creamy and satisfying.
Q4: Can I freeze this casserole?
Yes, you can freeze the baked casserole once cooled. Wrap tightly and freeze for up to 2 months. Reheat in the oven until hot throughout. Note: texture may change slightly, especially the topping.
Q5: How do I avoid a watery casserole?
Make sure to blanch and drain vegetables thoroughly to avoid excess moisture. Let the sauce thicken properly on the stovetop before assembling, and avoid covering the casserole while baking.
Q6: What can I use instead of breadcrumbs?
Crushed crackers, crushed nuts (like almonds or pecans), or even a gluten-free bread alternative can work. You can also top with extra cheese alone for a golden crust.
Q7: Can I serve this as a main dish?
Absolutely. Add a protein source like chickpeas or lentils and pair with a salad or grain-based side to make it a complete, filling vegetarian main for Christmas.
Creamy Veggie Casserole – A Cozy Vegetarian Christmas Dinner
- Total Time: 50 minutes
- Yield: 6–8 servings 1x
Description
A cozy, creamy vegetable casserole packed with seasonal veggies and topped with a golden, buttery crunch — perfect for a vegetarian Christmas dinner.
Ingredients
-
2 cups broccoli florets
-
2 cups cauliflower florets
-
1 cup sliced carrots
-
1 cup green beans, trimmed
-
1 cup mushrooms, sliced
-
1 small onion, diced
-
2 cloves garlic, minced
-
2 tbsp butter
-
2 tbsp all-purpose flour
-
1 cup whole milk
-
1 cup heavy cream
-
1½ cups shredded cheddar cheese
-
1 tsp fresh thyme
-
½ tsp dried sage
-
Salt & pepper to taste
-
1 cup breadcrumbs
-
2 tbsp melted butter (for topping)
-
Optional: parsley for garnish
Instructions
-
Preheat oven to 375°F (190°C). Grease a 9×13” baking dish.
-
Blanch broccoli, cauliflower, carrots, and green beans for 3–4 minutes. Drain and cool.
-
In a skillet, melt butter and sauté onion until soft. Add garlic and cook for 1 minute.
-
Stir in flour and cook for 2–3 minutes. Slowly whisk in milk and cream. Simmer until thick.
-
Add thyme, sage, salt, and pepper. Stir in shredded cheese until melted.
-
Combine vegetables and mushrooms in a bowl. Pour sauce over and mix gently.
-
Transfer to baking dish. Mix breadcrumbs with melted butter and sprinkle over top.
-
Bake for 25–30 minutes, until golden and bubbling. Broil for 2 minutes if needed.
-
Let rest for 10 minutes before serving.
Notes
-
Add lentils or chickpeas for protein.
-
Use vegan cream and cheese for a dairy-free version.
-
Swap breadcrumbs with crushed crackers or nuts for variation.
-
Leftovers keep in fridge for 3–4 days.
- Prep Time: 20 minutes
- Cook Time: 30 minutes
- Category: Main or Side
- Cuisine: Holiday / Vegetarian
Nutrition
- Calories: ~320 per serving