Vegan Potato Casserole features potatoes and leeks baked up in a dreamy, creamy, oil free vegan cheddar cheese sauce—made with your choice of cashews or chickpeas.
If you’ve ever loved au gratin potatoes, I think you’ll be over the moon for this cheesy potato casserole. It’s got a homemade, oil free vegan cheddar cheese sauce. None of that unhealthy store-bought stuff.
And you’ve got options here. Either go with the super rich and creamy cashew cheese version, or if nuts aren’t for you, the chickpea version (a lot like my chickpea cheese sauce recipe) is a great alternative. (Check out the nutritional info for both versions at the bottom of the page.)
I’ve tested both variations. While I personally love the more decadent cashew version, especially for a holiday dish, they’re both delicious and so satisfying.
If you haven’t tried chickpea sauces yet, check out my pasta carbonara or 5-minute Alfredo sauce. They’re quick and easy, full of fiber, low in fat, and really tasty!
How to Make This Cheesy Vegan Potato Casserole
The key to cooking this dish is getting thin, even potato slices (I used a mandoline), then pre-cooking them JUST A LITTLE so the casserole doesn’t take so long to cook. That helps keep the cheese sauce from drying out. And when you’re baking up several holiday dishes, you can be sure everything will be done at the same time.
Potatoes, leek, garlic, nutritional yeast, apple cider vinegar, tomato paste, broth & seasonings
What You Need to Make Vegan Au Gratin Potatoes
- Russet potatoes
- Leek
- Garlic
- Cashews (raw, unsalted) or chickpeas (canned or homemade)
- Nutritional yeast (I like Bragg’s)
- Vegan worcestershire sauce (watch out for anchovy paste)
- Tomato paste
- Low sodium vegetable broth (Make your own or buy boxed or powdered broth. For best results, taste it to make sure you like it before using in a recipe!)
- Apple cider vinegar
- Spices and seasonings (see recipe for full list)
Step-by-Step Guide to Making this Cheesy Potato Casserole
(See full recipe at the bottom of the page)
- First, prep the potatoes. Get a big pot of water boiling on the stove. Peel the potatoes (if you like), then cut into 1/8” slices using a mandoline or sharp knife. Cook for 3 minutes, drain and rinse in cold water. (See expert tips below.)
- Second, prep the leeks. Clean and slice them into 1/8 segments, then separate into rings. (See expert tips below.) Saute the leeks with garlic and set aside. Save some raw leek slices for garnish if desired.
- Third, make the cheese sauce. Soak cashews in hot water for 15 minutes. (Or, if using chickpeas, drain and rinse them.) Add them to a blender along with the other sauce ingredients, and process until smooth and creamy.
- Finally, assemble the casserole and bake. Mix the potatoes, sautéed leeks and garlic, and cheddar cheese sauce together in a bowl. Spread evenly in a 9″ x 13″ parchment paper-lined baking dish, top with some uncooked leek slices, cover and bake. Uncover at the end and bake 10 more minutes.
Slice the potatoes with a mandoline (or sharp knife)
Pre-cook the potato slices for 3 minutes
Fill a bowl with water to clean the leek slices
Saute the leeks and garlic
Process the cheddar cheese sauce ingredients in a blender until smooth and creamy
Gently toss the ingredients in a bowl, then spread evenly in a 9″ x 13″ baking dish
Expert Tips for Making this Recipe
- To slice potatoes with a mandoline. I found the best way to do this is to first cut each potato in half, then trim 3, 1/8″ slices off the tip of each potato with my knife. That gives you a flat surface to attach the vegetable holder part of the mandoline, and a flat surface on the mandoline’s blade. (See picture.)
- To slice potatoes with a knife. I prefer the mandoline because without thin even slices, this dish can take longer to cook and/or cook unevenly. But it is possible to do this with a very sharp knife. Just go slowly and be sure to keep checking the thickness of your potatoes so they’re as close to 1/8″ and even as you can get them.
- Pre-cooking the potatoes. This helps the dish cook more quickly and evenly. You don’t want them too soft, or they’ll break apart when you toss them in the cheese sauce. It’s also important to rinse them in cold water to stop the cooking (I used a colander) and be sure to pat them dry before adding to the mixing bowl so they don’t water down your sauce.
- To clean the leeks. Leeks can be full of dirt and sand, and can be tricky to clean. A neat trick is to swish your leek slices around in a bowl of water. The slices will float on the top and the dirt will fall to the bottom. Then, remove the clean slices, leaving the dirt behind. (See picture.)
- To slice the leeks. I can’t recommend using the mandoline, because I couldn’t figure out a way to do it safely, using the hand guard. (If you have a method, I’d love to hear it!) Use your very sharp knife and keep the slices 1/8” thick, just like the potatoes.
I’m sure ‘au gratin potatoes’ was the first French phrase I ever learned as a kid. My Mom’s favorite restaurant—a place called Charley O’s—served them in piping hot little white ramekins, broiled to lovely golden brown perfection. I swear can still taste those potatoes all these years later. Now that I’ve got this delectable vegan au gratin potatoes recipe, I can relive those memories any time.
Is there a recipe from your childhood that really takes you back? If so, drop me a note in the comment section below.
-Elizabeth xo
Check these holiday favorites: Vegan Porcini Mushroom Gravy, Vegan Sweet Potato Casserole, Healthy Twice-Baked Potatoes, Almond Ricotta, Easy Vegan Collard Greens, Instant Pot Collard Greens, Shaved Brussels Sprouts with Oil Free Citrus Dressing and Healthy Brownies with Peppermint Frosting and Healthy Apple Crisp-4 Ingredients.
I LOVE hearing from you! Connect with me on: Facebook, Instagram, Pinterest, or drop me a note in the comments.
Vegan Cheesy Potato Casserole
Equipment
- mandoline
- Blender
- Sharp knife
Ingredients
- 2 pounds russet potatoes 1/8 inch sliced and parboiled (about 3 potatoes)
- 1 leek 1/8 inch sliced (reserve some slices for garnish, if desired)
- 2 cloves garlic peeled, smashed and finely minced
Cheddar 'Cheese' Sauce (about 1 1/2 cups)
- 1 cup cashews soaked for 15 minutes in hot water. Or sub 1 1/2 cup cooked & rinsed chickpeas (1-15 ounce can) See 2nd recipe for nutritional info.
- 1 cup low sodium vegetable stock
- 2 tablespoons apple cider vinegar
- 1/4 cup nutritional yeast
- 1 tablespoon tomato paste
- 1 teaspoon vegan Worcestershire sauce
- 1/2 teaspoon smoked paprika
- 1/2 teaspoon onion powder
- 1/2 teaspoon garlic powder
- 1/4 teaspoon nutmeg
- Sea salt and freshly ground black pepper to taste
Instructions
- Pre-heat the oven to 350 degrees Fahrenheit.
To Prepare the Potatoes
- Peel the potatoes if desired. Then, use the 1/8" setting on a mandoline (or use a very sharp knife) and slice the potatoes into thin, even slices. (See recipe notes below for slicing tips.)
- Fill a large pot with water and heat to boiling. Add the potato slices and cook for 3 minutes. The slices should be just fork tender, but not cooked through yet. (See recipe notes.)
- Immediately drain in a colandar and rinse thoroughly with cold water to stop the cooking. (See recipe notes.) Pat the potato slices dry with a towel, and place them in a large mixing bowl.
To Prepare the Leeks
- Slice the leeks width-wise into 1/8" rings. Fill a mixing bowl with water and add the leeks to the bowl. Stir with your hand to allow the dirt to fall to the bottom of the bowl, separating the leek segments into rings as you go. Carefully remove just the cleaned leek rings from the bowl, allowing the dirt behind, and set aside. (If desired, set aside a couple tablespoons of leek rings to top the casserole.)
- In a small saute pan, heat a tablespoon or so of water on medium high heat. Add the leeks and saute until just tender, about 5 minutes. Add more water a little at a time if things begin to stick. Add the garlic and saute 2 more minutes. Add the leeks and garlic to the mixing bowl with the potato slices.
To Make the Cheese Sauce
- Add your soaked cashews (or chickpeas, if using) and all of the other Cheddar Sauce ingredients to a high powered blender, and process until thick and creamy. Scrape down the sides as needed. Add the cheese sauce the to mixing bowl wtih the potatoes, garlic and leeks.
To Assemble the Casserole
- Gently toss the cheese sauce, potatoes, garlic and leeks together, being careful not to break apart the potates. Make sure all of the ingredients are coated with cheese sauce. You may have to use your hands to separate the leek slices and distribute them through the bowl.
- Line a 9" x 13" baking dish with parchment paper. (Not absolutely necessary, but much easier for clean up.)
- Carefully spread out the potato slices in the baking dish. Use a rubber scraper to scrape any excess cheese sauce from the bowl and spread it on top of the potatoes.
- Cover with aluminum foil and bake for 30-40 minutes at 350 degrees Fahrenheit, or until the potatoes are fork tender. Remove the foil, add the reserved leeks as garnish, and bake 10 more minutes.
Notes
Nutrition
Vegan Cheesy Potato Casserole (Made with Chickpea Cheese Sauce)
Ingredients
- 2 pounds russet potatoes 1/8 inch sliced and parboiled (about 3 potatoes)
- 1 leek 1/8 inch sliced (reserve some slices for garnish, if desired)
- 2 cloves garlic peeled, smashed and finely minced
Cheddar 'Cheese' Sauce (about 1 1/2 cups)
- 1 1/2 cup cooked chickpeas, drained and rinsed 1-15 ounce can
- 1 cup low sodium vegetable stock
- 2 tablespoons apple cider vinegar
- 1/4 cup nutritional yeast
- 1 tablespoon tomato paste
- 1 teaspoon vegan Worcestershire sauce
- 1/2 teaspoon smoked paprika
- 1/2 teaspoon onion powder
- 1/2 teaspoon garlic powder
- 1/4 teaspoon nutmeg
- Sea salt and freshly ground black pepper to taste
Instructions
Prepare according to recipe instructions above.
Nutrition
How many degrees oven should be?thanks
So sorry I missed that! It’s 350 degrees Fahrenheit. I’ve added to the recipe. Thanks!
Thank you! We cooked at 200 degrees Celsius, tasty! Thank you for the recipe!we will definitely make again. Maybe also add how many degrees in Celsius:D
That’s a great suggestion! I’ll try to remember to add that in the future, thanks 🙂
We are going to attempt this for our (Canadian) Thanksgiving. Thank you so much for sharing.
You’re so welcome. Hope it’s a hit!
Thank you for creating a vegan cheese sauce using chickpeas! Most such recipes call for cashews, but my husband is allergic to those. This looks delicious, she we’re looking forward to trying it!
You’re so welcome, Kim! I hear from a lot of readers who are either allergic or trying to limit fat in their diets. I created recipes like my chickpea cheese sauce for people avoiding nuts. You and your husband must not be alone because it’s my most popular recipe with over 15,000 shares on social media!