This irresistible vegan cauliflower gratin recipe is incredibly quick and easy to make. No need to pre-cook the sauce or cauliflower; simply toss ingredients into the casserole dish! This is the perfect cheesy baked cauliflower, loaded with flavor that pairs well with almost any main dish.
Skill Level: Easy | Time: 55 minutes | Servings: 4
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Is Cauliflower au Gratin Vegan?
Cauliflower au gratin is a common side dish (or main course) 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 that classically rich and satisfying cheese sauce.
I also add plenty of herbs and spices to cauliflower gratin whereas traditional recipes are plain and 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 to Make Vegan Cauliflower Casserole
To create a flavorful vegan cauliflower cheese casserole with rich and creamy sauce, this recipe uses a few ingredients that may be unconventional but work well together.
- Cauliflower: The star of the show! Cauliflower is a delicious cruciferous vegetable and despite being white in color, it’s loaded with nutrients. I always buy the biggest cauliflower I can find, and half of a large head is plenty for this recipe. There’s lots of other delicious cauliflower recipes you can make with the extra (or double the recipe here!).
- Vegan butter or margarine: To make this a rich and creamy gratin, vegan butter (or margarine) provides some much needed flavor and fat! It’s melted with the garlic, creating a quick and simple garlic butter that becomes the sauce’s base.
- Garlic: I can’t cook without garlic, and lots of it! Mince it well and use as much or little as you like.
- Soy milk: Soy milk is my favourite plant-based milk since I find it’s the creamiest and most delicious. It’s also what I keep on hand and is the plant-based milk I use in pretty much any recipe. Other plant-based milk options should work, but I haven’t tested them.
- Starch: To thicken the sauce, add corn starch and whisk it into the sauce well so there aren’t any clumps! I use corn starch because it’s easy to find and super cheap!
- Nutritional yeast: Nutritional yeast, aka nooch, is a staple in my vegan kitchen. It adds lots of delicious cheesy flavor to the recipe, which I find necessary since many vegan cheese options lack flavor for my tastes. Nutritional yeast is often fortified and can also be a great source of vitamin B12 for vegans!
- Dijon mustard: Some Dijon goes a long way to add depth of flavor to the cheesy gratin sauce.
- Onion powder: Since we don’t use fresh onion in this recipe, onion powder brings a good flavor to the sauce.
- Salt and pepper: Salt and pepper are essential for most recipes. Depending on how salty the vegan cheese you use is, you may need to add more to satisfy your taste preferences.
- Dry oregano and basil: These two herbs are a delicious combination but aren’t always included in a cauliflower gratin. I love adding herbs to most recipes, but you can do without if you’re looking for a more classic gratin flavor.
- Smoked paprika: Smoked paprika is probably one of my favorite spices and I use it in so many recipes. It’s not a traditional gratin ingredient and the smoky flavor certainly comes through. If you’re not a fan, skip the smoked paprika or use a regular paprika instead. I love adding paprika to most cheesy/ creamy sauces for a boost of flavor and color.
- Apple cider vinegar: Vinegar adds some acidity to this recipe which elevates other flavors. Lemon juice is also a good choice if you have it on hand!
- Vegan cheese shreds: To make this a truly cheesy sauce, add vegan shredded cheese! If possible, use a brand that melts well for a smoother sauce.
How to Make Vegan Baked Cauliflower Casserole: Instructions and Video Tutorial
This baked cauliflower casserole is incredibly simple to make. Unlike many other cauliflower casserole recipes, the cauliflower doesn’t need to be pre-cooked and neither does the sauce!
The cauliflower comes out perfectly cooked, with some “bite” left to it (meaning it isn’t complete mush and has a delicious texture).
Step 1: Prep the Cauliflower
To start, preheat the oven to 375 °F and cut the cauliflower into bite-sized pieces. Select a small to medium-sized casserole dish and toss the cut cauliflower pieces directly into the dish.
It’s best to use a casserole dish that has a lid. If you don’t have a lid for your dish, use tin foil to cover the top of the gratin while it bakes. This helps retain liquid content and creates a creamier, saucier gratin.
Step 2: Make the Sauce
To make the sauce, add vegan butter (or margarine) to a microwave-safe bowl along with minced garlic. Microwave for 30-45 seconds, until the butter completely melts.
Next, whisk in soy milk and starch. After there are no more clumps of starch, whisk in the remaining sauce ingredients.
Step 3: Combine, Bake and Serve
Pour the sauce into your cauliflower-filled casserole dish. Stir to coat the cauliflower with the cheese sauce. Place the lid (or tin foil) on the baking dish and place into a preheated oven for 25 minutes.
Remove the gratin from the oven, stir the cauliflower around to ensure the sauce is coating the top pieces of cauliflower, then place the lid (or tin foil) back onto the dish and bake for another 15 minutes.
Remove from the oven and serve hot!
Vegan Cheesy Cauliflower Bake Tips, Substitutions and Variations
While this recipe is easy to make, keep in mind these tips:
- If possible, select vegan cheese shreds that melt. Vegan cheese can be difficult to melt, but when added to a sauce, it tends to melt more easily. You can microwave the sauce before pouring it over cauliflower, if needed, to help the cheese melt.
- Don’t skip the starch. Starch is necessary to thicken the sauce and it’s likely to be thin or runny without. I use corn starch because it’s easy to find, cheap and effective. Whisk the starch into the sauce until there aren’t any clumps of starch, otherwise the final sauce will have clumps and not thicken properly.
- Adjust seasoning to your taste. I love smoked paprika, but it’s not for everyone, especially since it’s not a common ingredient in gratin. If you prefer, use a regular paprika or leave this ingredient out completely. You can also adjust the garlic, onion powder, oregano and basil to your liking. Oregano and basil aren’t super common in gratin recipes, but I love the flavor they bring!
- Bake with a lid or foil sheet on the casserole dish. Since the cauliflower isn’t pre-cooked, this traps steam and allows the cauliflower to cook thoroughly (but it holds it’s texture and won’t be mushy!).
How to Store Cauliflower Gratin: Refrigerating and Freezing this Recipe
Refrigerate any leftover gratin in an airtight container for up to a week. It’s easy to reheat the cauliflower gratin in single portions on a plate in the microwave.
You can prepare the gratin up to a day ahead of baking. Simply cut the cauliflower, make the sauce, toss together, and store the casserole dish (with the lid on) in your fridge until ready to bake.
I hope you enjoy this easy vegan cauliflower gratin recipe as much as I do. If you make this recipe and share your creations on Instagram, tag me @lettucevegout because I love seeing what you make!
Vegan Cauliflower Gratin
- Cutting Board
- Microwave safe bowl
- Small casserole dish (with lid)
- ½ large head cauliflower (5 – 6 cups chopped)
- ¼ C vegan butter (or margarine)
- 3 large cloves garlic , minced
- 1 C soy milk (or plant-based milk of choice)
- 1 tbsp corn starch
- ¾ C shredded vegan cheese
- 1 ½ tbsp nutritional yeast
- 1 tsp Dijon mustard
- ½ tsp onion powder
- ¼ tsp salt (or to taste)
- ⅛ tsp black pepper
- ¼ tsp smoked paprika (or regular paprika)
- ¼ tsp dry oregano
- ¼ tsp dry basil
- ½ tsp apple cider vinegar
- Preheat oven to 375 °F.
- Prep cauliflower by cutting it into bite-sized pieces, then place cut cauliflower into casserole/ baking dish.
- Add the vegan butter (or margarine) to a microwave safe bowl along with the 3 cloves of minced garlic. Melt in the microwave for 30-45 seconds (until butter is liquid).
- Whisk the 1 C soy milk and 1 tbsp corn starch into the butter until there are no visible clumps of starch.
- Next, whisk the remaining ingredients into the sauce: ¾ C shredded vegan cheese, 1 ½ tbsp nutritional yeast, 1 tsp Dijon mustard, ½ tsp onion powder, ¼ tsp salt (or to taste), ⅛ tsp black pepper, ¼ tsp smoked paprika (or regular paprika), ¼ tsp dry oregano, ¼ tsp dry basil and ½ tsp apple cider vinegar.
- Pour the sauce over the cauliflower and stir to coat cauliflower with sauce. Place lid onto casserole dish (or tin foil if dish doesn’t have lid) and bake for 25 minutes.
- Remove cauliflower gratin from the oven, stir well (make sure top pieces of cauliflower are coated with sauce), place lid back onto dish and bake another 15 minutes.
- Once baked, the gratin is ready to serve!