Looking for a side dish that’s as comforting as mashed potatoes but low in carbs and full of flavor? Look no further than this Cheesy Zucchini Gratin. This indulgent, golden-topped casserole is packed with thinly sliced zucchini, sautéed onions, rich garlic, and a velvety cheese sauce that bubbles up into something insanely yummy.
Even better? It’s simple enough for a weeknight dinner, but impressive enough for holiday tables or entertaining guests. The combination of garlic, Parmesan, and a mix of melty cheeses creates a gratin that’s elegant, satisfying, and keto-friendly—without sacrificing the indulgent taste and texture of traditional creamy casseroles.
🛒 Ingredients – What You’ll Need
All of the ingredients are easy to find, and many are likely already in your fridge or pantry. This recipe is highly flexible, so feel free to swap cheeses or tweak seasonings to your taste.
Ingredients List:
- 1 large zucchini, sliced thin & cut in half circles
- ½ cup freshly grated Parmesan cheese
- 4 tablespoons butter
- 1 small onion, sliced thin
- ¼ cup beef broth
- 1 cup cheese of your choice (mozzarella and Asiago mix recommended)
- 3 large cloves garlic, minced
- ½ teaspoon salt
- ½ teaspoon pepper
- ½ cup heavy cream
💡 Try using a mandoline for evenly sliced zucchini—it helps the gratin cook evenly and creates a lovely layered texture.
👩🍳 Instructions – How to Make Cheesy Zucchini Gratin
This dish starts on the stovetop and finishes in the oven. Be sure to use an oven-safe skillet, like cast iron, to make the transition from sautéing to baking a breeze.
Step-by-Step Directions:
- Preheat the oven to 425°F (220°C).
- In a large oven-proof skillet, melt the butter and sauté the thinly sliced onion until lightly caramelized—about 5 to 7 minutes over medium heat.
- Add in the minced garlic and cook for an additional minute until fragrant.
- Pour in the beef broth, salt, pepper, and heavy cream. Stir well to combine.
- Let the mixture come to a gentle simmer, then stir in the Parmesan cheese until melted and smooth.
- Add in the sliced zucchini, cooking for about 5 minutes, stirring occasionally, until the zucchini begins to soften.
- Sprinkle the cheese mix evenly over the top.
- Transfer the skillet to the oven and bake for 12–15 minutes, or until the cheese is bubbly and golden brown to your liking.
- Remove from the oven, let cool slightly, and serve hot!
🧀 Why You’ll Love This Zucchini Gratin
- Low-carb and keto-friendly: No breadcrumbs, no flour—just veggie goodness and cheesy delight.
- Packed with garlic and onion flavor: Every bite is savory and satisfying.
- Incredibly versatile: Works as a side dish or even a light vegetarian main.
- One-skillet meal: Easy to make and easy to clean up.
🍴 Serving Suggestions
This Cheesy Zucchini Gratin pairs beautifully with:
- Grilled meats: Try it with steak, chicken thighs, or pork chops.
- Holiday roasts: A perfect vegetable side dish for Thanksgiving, Easter, or Christmas.
- Low-carb dinners: Serve alongside cauliflower mash or keto breadsticks for a full keto meal.
- Vegetarian plate: Enjoy as a main dish with a crisp green salad or roasted vegetables.
🔁 Recipe Variations
Want to make it your own? Try one of these tasty twists:
- Add protein: Stir in shredded rotisserie chicken or cooked crumbled sausage for a heartier version.
- Swap the cheese: Gouda, fontina, gruyere, cheddar, or provolone all melt beautifully.
- Add herbs: Mix in fresh thyme, rosemary, or parsley for a more herbaceous flavor.
- Make it spicier: Add crushed red pepper flakes or diced jalapeños.
🥓 Pro Tip: Top with a sprinkle of crispy bacon before serving for an extra savory kick.
⏱ Recipe Summary
| Prep Time | Cook Time | Total Time | Servings |
|---|---|---|---|
| 10 minutes | 20 minutes | 30 minutes | 4–6 |
🧊 Storage & Reheating Tips
- To store: Let the gratin cool completely. Transfer to an airtight container and refrigerate for up to 3 days.
- To reheat: Warm in a 350°F oven for 10–15 minutes or microwave individual portions in 30-second intervals until hot.
This dish reheats beautifully—perfect for meal prep or enjoying the next day!
🌟 Final Thoughts
Creamy, cheesy, garlicky, and totally comforting, this Cheesy Zucchini Gratin is a total winner for both veggie lovers and skeptics alike. It’s the kind of dish that feels indulgent but is surprisingly simple and wholesome. Whether you’re serving it as a side or the star of the plate, it’s bound to be a repeat favorite.
It’s keto-friendly, gluten-free, and guaranteed to wow your guests or family.
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🧀 Cheesy Zucchini Gratin – Low Carb, High Flavor Comfort Food!
Cheesy Zucchini Gratin is not only low carb, but it is insanely yummy and loaded with garlic and the most delicious cheesy cream sauce!
Ingredients
1 large zucchini, sliced thin & cut in half circles
1/2 cup freshly grated Parmesan cheese
4 tablespoons butter
1 small onion, sliced thin
1/4 cup of beef broth
1 cup cheese of your choice (I used mozzarella and Asiago mix)
3 large cloves of garlic, minced
1/2 teaspoon of salt
1/2 teaspoon pepper
1/2 cup heavy cream
Instructions
In a large oven proof skillet, melt butter with the onions until lightly caramelized, then add in the fresh garlic and saute for about 1 minute on medium heat.
Add in the beef broth, salt, pepper and the heavy cream into the onion/garlic mixture and stir to combine.
Allow it to slightly begin to bubble, then add in the Parmesan cheese and stir. Add in the sliced zucchini and cook an for an additional 5 minutes until softened.
Top with your cheese of choice evenly across the entire top and bake at 425F for about 12-15 minutes or until the cheese begins to brown to your liking
Notes
| Prep Time | Cook Time | Total Time | Servings |
|---|---|---|---|
| 10 minutes | 20 minutes | 30 minutes | 4–6 |