This vegan cauliflower gratin recipe creates an ultra-cheesy, rich and delicious baked casserole. It’s super easy to make with no need to pre-cook the sauce or cauliflower!
It’s also a perfect side dish, especially for holiday meals. It’ll impress anyone who tries it, vegan or otherwise!
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Is Cauliflower au Gratin Vegan?
Cauliflower au gratin is a common side dish that’s made by baking cauliflower in a cheesy sauce. Typical gratin recipes are not vegan since they contain dairy.
To make vegan cauliflower gratin, you’ll need plant-based milk and cheese shreds for a rich and satisfying cheese sauce.
I also add plenty of herbs and spices to cauliflower gratin whereas traditional recipes are relatively simple (but still delicious). The herbs and spices in this recipe (basil, oregano and smoked paprika) are optional, so adjust to your own taste preferences.
Ingredients for Vegan Cauliflower Casserole
To create a flavorful vegan cauliflower cheese casserole with creamy sauce, this recipe uses a few ingredients that may be unconventional but work well together.
- Cauliflower: You’ll need one small head of cauliflower for this recipe, or half of a large cauliflower. This delicious vegetable has a mild flavor that’s enhanced by cooking, and despite being white, it’s actually very nutritious.
- Vegan butter: The sauce uses garlic butter for a rich and creamy gratin. You can use vegan margarine if you prefer.
- Garlic: I love garlic and lots of it! This adds tons of flavor to a cauliflower bake, so don’t hold back!
- Soy milk: The sauce needs creamy liquid and I like to use soy milk. Soy milk is richer and creamier than most other plant-based milks. Technically any plant-based milk should work, but I haven’t tested the recipe with other options.
- Corn starch: This essential ingredient helps the sauce thicken as your casserole bakes. I haven’t tested other starch options, but they may work.
- Vegan cheese shreds: For a cheesy casserole, vegan cheese shreds work well. Vegan cheese is notorious for not melting, but in a sauce, most brands seem to melt okay. Use your favorite dairy free cheese shreds; I use a cheddar-style for this recipe!
- Nutritional yeast: Even though you’ll use vegan cheese in this recipe, boost the savory, cheesy flavor with some nutritional yeast too.
- Dijon mustard: While this is optional, it adds a nice flavor and some “zing” to the sauce.
- Apple cider vinegar: If you’ve ever roasted or baked veggies and thought they lacked something, it likely didn’t have vinegar (or another acidic ingredient). Acidity always enhances a recipe and elevates other flavors. Any type of vinegar can work but I use apple cider vinegar and always have some on hand.
- Onion powder: Since this recipe doesn’t use fresh onion, some onion powder helps bring in that delicious flavor.
- Smoked paprika: This smoky spice adds tons of flavor to cauliflower bake. While it’s not a traditional ingredient, I love it. A regular, sweet or even spicy paprika can work; or skip it entirely for a classic flavor.
- Dry oregano and basil: These two herbs are optional, but I love how they boost flavor in this recipe. They aren’t traditional cauliflower gratin ingredients, so skip them if you want that simple, classic flavor.
- Salt and pepper: Round out the recipe with salt and black pepper, added to your taste. Don’t skimp on the salt; cheese is very high in salt and is essential to getting the right flavor when making vegan cheese alternatives.
How to Make Cheesy Cauliflower Bake
This baked cauliflower casserole is incredibly simple to make. Unlike other cauliflower casserole recipes, you don’t need to pre-cook the cauliflower or the sauce!
Your cauliflower will come out perfectly cooked, with some “bite” left to it (meaning it isn’t complete mush and has a delicious texture).
Step 1: Prep Cauliflower
Begin by preheating your oven to 375 °F.
Cut the cauliflower into small, bite-sized pieces. Add the cauliflower pieces into a small to medium-sized baking dish.
Any baking dish that holds the cauliflower should work. If you have a casserole dish with a lid, that’s best to use. Otherwise, use tin foil to cover the gratin while it bakes.
Step 2: Prep Sauce
Prepare the cheesy sauce by adding vegan butter to a microwave-safe container along with minced garlic. Microwave the butter in 30-45 second intervals. Once it’s melted, use your delicious garlic butter as the sauce base.
Next, add plant-based milk and starch. Whisk this mixture until there are no clumps of starch left. Use a small whisk or a fork.
Then add the remaining sauce ingredients, including shredded vegan cheese, nutritional yeast, Dijon mustard, apple cider vinegar, onion powder, salt, smoked paprika, dry oregano, dry basil and black pepper.
Remember, you can adjust the seasonings to your taste.
Stir the sauce until everything is well combined.
Step 3: Assemble and Bake
Pour sauce over your cauliflower in the baking dish. Toss to coat the cauliflower with sauce.
Place a lid on the baking dish (or tin foil if there isn’t a lid) and place into your preheated oven.
Bake for 50 minutes total. At the halfway point, remove your casserole from the oven and stir it. This helps cook the cauliflower and sauce evenly. You may find it best to stir the dish around twice through the baking process.
Don’t forget to stir your cauliflower! I recommend setting a timer to 25 minutes, stir, then return the lid (or tin foil) to your baking dish before putting it back in for another 25 minutes.
The cauliflower is ready when it’s fork tender but still has a slight crunch. If you prefer your cauliflower more well-done, bake it for longer.
The cheesy sauce should also be thick and creamy when done.
You can serve this dish hot, straight from the oven.
How to Serve this Vegan Cauliflower Gratin
Cauliflower gratin is a side dish that mainly provides a vegetable and fats. Aim to serve it alongside some protein and carbohydrates.
Herbed focaccia bread or whole wheat dinner rolls are tasty, homemade bread options if you want a boost of carbohydrates. Mashed or roasted potatoes (or sweet potatoes) are also a tasty side dish alongside cheesy cauliflower bake.
How to Refrigerate Baked Cauliflower
Let leftovers cool to about room temperature before transferring to an airtight container. Alternatively, you can simply cover the baking dish and, once cooled, place in your fridge. You can refrigerate this dish for up to 5 days.
Reheat using a microwave or oven, set to 350 °F, until warmed through (use a lid/ tin foil when reheating so it doesn’t dry out). If you want to prep the recipe one day and cook it the next, store uncooked casserole covered in your fridge.
When ready to bake, simply place into a preheated oven. The dish may take 5-10 minutes longer to cook if you do this because the baking dish and all the ingredients start cold.
If you make this recipe, please rate and comment below to help others benefit from your experience!
Vegan Cauliflower Gratin
- Microwave safe bowl (or small pot)
- Small casserole dish (with lid or tin foil)
- Whisk (or fork/ spoon)
- 5 cups cauliflower , cut into florets (~1 small head; 1 cup = 110 g)
- ¼ cup vegan butter , or margarine (60 g)
- 3-4 cloves garlic , mined or crushed
- 1 cup plant-based milk , I use soy milk
- 1 tablespoon corn starch
- ¾ cup vegan cheese , shredded (70 g)
- 1 ½ tablespoons nutritional yeast
- 1 teaspoon Dijon mustard
- ½ teaspoon apple cider vinegar
- ½ teaspoon onion powder
- ¼ teaspoon salt
- ¼ teaspoon smoked paprika
- ¼ teaspoon dry oregano
- ¼ teaspoon dry basil
- ⅛ teaspoon ground black pepper
Step 1: Prep Cauliflower
- Preheat your oven to 375 °F.
- Cut cauliflower into bite-sized pieces.5 cups cauliflower
- Add cauliflower pieces to a small-medium sized baking dish (any dish that fits the cauliflower). A dish with a lid is best.
Step 2: Prep Sauce
- Add vegan butter to a microwave-safe dish along with minced garlic. Microwave in 30-45 second intervals until the butter melts completely.¼ cup vegan butter, 3-4 cloves garlic
- Add soy milk and corn starch to the butter (use larger bowl if needed). Whisk until there are no clumps of starch left (use a small whisk or fork).1 cup plant-based milk, 1 tablespoon corn starch
- Add remaining sauce ingredients to the milk mixture: vegan cheese shreds, nutritional yeast, Dijon mustard, apple cider vinegar, onion powder, salt, smoked paprika, dry oregano, dry basil and ground black pepper.¾ cup vegan cheese, 1 ½ tablespoons nutritional yeast, 1 teaspoon Dijon mustard, ½ teaspoon apple cider vinegar, ½ teaspoon onion powder, ¼ teaspoon salt, ¼ teaspoon smoked paprika, ¼ teaspoon dry oregano, ¼ teaspoon dry basil, ⅛ teaspoon ground black pepper
- Stir or whisk until well combined.
Step 3: Assemble and Bake
- Pour sauce over your cauliflower in the baking dish. Stir to coat cauliflower in sauce.
- Place a lid on the baking dish (or tin foil if there isn’t a lid) and bake for 50 minutes total. Stir the cauliflower at least once, if not twice, during the cooking process. I recommend setting the timer to 25 minutes, stirring, then set for another 25 minutes.
- Return the lid/ tin foil to the baking dish before putting back into your oven.
- The cauliflower is done when it’s fork tender but still has a slight crunch to it (if you prefer it to be softer, cook longer). The sauce should be thick and creamy too.
- Serve hot.
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About Nicole Stevens
Nicole is a vegan Registered Dietitian (RD) and founder of Lettuce Veg Out.
She helps people thrive on a vegan diet with balanced recipes and easy-to-understand nutrition science.