Paleo Zucchini Gratin Casserole is healthy comfort food at it's very best. This hearty Whole30-friendly dish is creamy, "cheese-y" and absolutely delicious despite being dairy-free! Whether you're serving this elegant casserole as a side dish or the main course, it will surely have your family going in for seconds.
If you love zucchini, this easy gluten-free and dairy-free variation of Zucchini Au Gratin is going to rock your world. We eat quite a bit of zucchini in my house, and this flavorful recipe has quickly become our absolute favorite way to enjoy it (Zucchini Fries are a very close second)!
The velvety cream sauce paired with fresh zucchini and a crispy grain-free cracker crumb crust makes for the ultimate comfort food.
Lucky for us zucchini advocates, it's pretty easy to come by all year long, so this casserole is great for almost every holiday family gathering.
Did I mention how easy this casserole is? No? Well, IT'S SUPER EASY, so let's get cooking!
Ingredients for Gluten-Free & Dairy-Free Zucchini Gratin Casserole
A traditonal au Gratin style casserole is sprinkled with cheese and breadcrumbs. This recipe pays tribute to a classic with dairy-free, gluten-free and grain-free ingredients, but do not let that deter you. This comforting casserole is aimed to impress even the most skeptical of special diets (i.e. Keto, Paleo and Whole30). Let's chit-chat about the ingredients.
Zucchini - You'll need about two pounds of fresh zucchini. I used 5 smaller zucchini equaling roughly two pounds. Once sliced, you should have about 4 cups of ¼" thick zucchini rounds.
Ghee - The rich flavor of ghee gives this dish so much buttery flavor, and who doesn't love butter?
Mayonnaise - So you have two options when it comes to the mayonnaise you use. If you're Keto, Paleo or Whole30, make sure the mayo you use is sugar-free and compliant. Better yet, just make your own! There's quite the selection of homemade mayonnaise recipes on the Internet (all of which will result in a mayo-like substance), but the Whole30 recipe is my absolute favorite!
Nutritional Yeast - What would I do without this stuff? It's my secret weapon whenever I want to develop a rich cheese-y flavor without any cheese!
Dried Onion Flakes, Salt, Garlic Powder, Onion Powder, Parsley, Celery Seed & Pepper - I have an aunt that brings a scalloped potato dish to our annual Christmas Eve party every year. She uses one of those packets of dry onion soup mix to amp up the flavor, and dang it's good. With that in mind, I replicated the bold flavors of dry onion soup mix with this blend of herbs and spices. Your taste buds are in for a real treat.
The Best Grain-Free Crackers for Paleo Zucchini Gratin Casserole
I used crushed Simple Mills Rosemary & Sea Salt Almond Flour Crackers for the crumbly topping, but I'm sure any flavor of Simple Mills Crackers would work just as well (every flavor is delicious). I love Simple Mills because they're grain-free and Paleo-friendly, but feel free to use your favorite gluten-free cracker instead.
How to Make Paleo Zucchini Gratin Casserole
Recipes created from real food ingredients sometimes take a bit of effort. Not this one. IT'S SO EASY.
First things first, preheat your oven to 375° while you assemble the casserole. For the zucchini, you'll want to slice it into ¼" thick rounds. In a large oven-safe skillet, cook the zucchini in ghee until tender-crisp, which will only take a few minutes. Remove the skillet from the heat promptly once the zucchini has cooked through a bit.
While the zucchini cooks, make the sauce by simply whisking together the remaining ingredients (except for the crackers) until smooth and creamy. Moving along, add the sauce to the skillet with the zucchini and gently toss to combine.
Move the skillet to your oven and bake for 10 minutes. After 10 minutes, sprinkle the cracker crumbs on top of the zucchini mixture and continue to bake the casserole for an additional 20 minutes or until the cracker crumb topping reaches the brownness of your liking -and just like that, your yummy casserole is complete! Told ya it was easy!
Egg-Free & Vegan Zucchini Gratin Variation
With a few simple swaps, this casserole can be made completely Vegan-friendly. Use your favorite plant-based buttery spread in place of ghee, egg-free Vegan mayo in place of regular mayo and a flax egg or store-bought Vegan egg replacement in place of the egg.
Will you be adding this comforting casserole to your next holiday meal spread? If so, I'd love to hear all about it! Sound off in the comments and feel free to tag me in your foodie photos @paleoishkrista with #paleoishkristaeats. Feast on, my friends.
PIN NOW! DO IT LATER!
Hungry for more comforting dairy-free, grain-free and veggie-loaded casseroles? Have at it.
- Vegan Roasted Root Vegetable Gratin
- Paleo Turkey and Broccoli Divan Casserole
- Whole30 Loaded Brunch Casserole
Paleo Zucchini Gratin Casserole
- 2 pounds zucchini
- 2 tablespoons ghee
- ½ cup mayonnaise store-bought or homemade
- ¼ cup nutritional yeast
- 1 egg
- 2 tablespoons dried onion flakes
- 1 teaspoon salt
- ½ teaspoon garlic powder
- ½ teaspoon onion powder
- ½ teaspoon parsley (dried)
- ¼ teaspoon celery seed
- ¼ teaspoon pepper
- 1 cup Paleo-friendly crackers i.e. Simple Mills Rosemary & Sea Salt Almond Flour Crackers
- Preheat oven to 375°. Wash and dry zucchini. Trim ends (discard) and slice the rest of the zucchini into ¼" thick rounds.
- Melt 2 tablespoons ghee over medium heat in a large oven-safe skillet (a cast-iron works great).
- While the ghee melts, prepare the sauce. In a medium bowl, whisk together mayonnaise, nutritional yeast, egg, dried onion flakes, salt, garlic powder, onion powder, parsley, celery seed and pepper. Whisk until smooth and creamy.
- Once the ghee has melted, add sliced zucchini to the skillet and cook until tender-crisp (4 to 5 minutes). Zucchini should still have a bite to them. Remove skillet from heat.
- Pour sauce into the skillet with the zucchini and toss gently to combine. Bake in preheated oven for 10 minutes.
- Meanwhile, break crackers into crumbs. After 10 minutes, remove the skillet from the oven, sprinkle cracker crumbs on top and return to the oven for an additional 20 minutes or until the cracker crumbs are golden brown and toasted. Paleo Zucchini Gratin Casserole is best served immediately. ENJOY! 🙂
Hungry for more? Don't forget to subscribe to my mailing list on your way out. You'll receive my monthly newsletter straight to your inbox! I can't wait to connect with you!