This Cheesy Kohlrabi Gratin is a delicious low-carb twist on the classic potato-based dish. With thinly sliced kohlrabi layered in a creamy cheese sauce and baked until golden and bubbly, it’s the perfect comforting side or light vegetarian main. Ideal for those looking to enjoy a rich and hearty dish without the carbs.

FULL RECIPE

Ingredients

• 3 medium kohlrabi bulbs, peeled and thinly sliced
• 1 tablespoon butter
• 1 small onion, finely chopped
• 2 cloves garlic, minced
• 1 cup heavy cream
• 1/2 cup whole milk
• 1 teaspoon Dijon mustard
• 1/2 teaspoon salt
• 1/4 teaspoon ground black pepper
• 1/4 teaspoon ground nutmeg (optional)
• 1 cup grated Gruyère cheese
• 1/2 cup grated Parmesan cheese
• 1 tablespoon chopped fresh parsley (optional, for garnish)

Directions

1. Preheat oven to 375°F (190°C). Grease a medium baking dish.
2. In a skillet over medium heat, melt the butter. Sauté the chopped onion until translucent, about 5 minutes. Add garlic and cook for another minute.
3. Stir in the heavy cream, milk, Dijon mustard, salt, pepper, and nutmeg. Bring to a gentle simmer, then remove from heat.
4. In the prepared baking dish, layer half of the sliced kohlrabi. Pour over half the cream mixture, then sprinkle with half the Gruyère and Parmesan cheeses.
5. Repeat with the remaining kohlrabi, cream mixture, and cheeses.
6. Cover with foil and bake for 30 minutes. Remove foil and continue baking for another 20–25 minutes, until golden and bubbling.
7. Let rest for 10 minutes before serving. Garnish with chopped parsley if desired.

Nutrition Facts

• Calories: 290
• Total Fat: 23g
• Saturated Fat: 14g
• Cholesterol: 70mg
• Sodium: 390mg
• Total Carbohydrates: 10g
• Dietary Fiber: 3g
• Sugars: 4g
• Protein: 11g
• Net Carbs: 7g

Why Use Kohlrabi Instead of Potatoes

Kohlrabi is an excellent low-carb substitute for potatoes in traditional gratin recipes. Its mild, slightly sweet flavor becomes tender and buttery when baked, mimicking the comforting texture of cooked potatoes without the heaviness. For those following ketogenic or low-carb diets, swapping potatoes with kohlrabi significantly reduces the carbohydrate content while still offering a satisfying bite. Additionally, kohlrabi is packed with fiber and antioxidants, making it not only a lighter option but also a more nutrient-dense one. Its subtle flavor also allows the cheese and cream to take center stage, giving this gratin a rich yet balanced taste.

Health Benefits of Kohlrabi

Kohlrabi is a cruciferous vegetable, part of the same family as broccoli, kale, and cabbage. It’s rich in vitamin C, providing over 100% of the daily requirement in just one cup. This supports immune function and skin health. It’s also a good source of dietary fiber, aiding in digestion and promoting a healthy gut. With very few calories and carbohydrates, kohlrabi is an ideal vegetable for weight management and blood sugar control. Its phytonutrients have been linked to reduced inflammation and a lower risk of chronic illnesses such as heart disease and certain cancers, making it a powerful yet underrated addition to your diet.

Best Cheese Options for Gratin

While Gruyère and Parmesan are traditional choices that lend excellent meltability and flavor, this gratin can be customized using other cheeses based on personal taste. Gruyère is known for its nutty, slightly salty flavor and creamy melt, making it perfect for gratin layers. Parmesan adds sharpness and depth, as well as a slightly crispy top when baked. Alternatives include white cheddar for a tangier flavor, Fontina for extra creaminess, or mozzarella for a milder, more elastic texture. Mixing two or more cheeses creates a more complex flavor profile and can help balance richness with sharpness in the dish.

Cream vs. Milk: What’s the Right Ratio

In gratin recipes, the balance of cream to milk determines both richness and texture. Too much cream can make the dish overly heavy, while too much milk might result in a watery sauce that doesn’t hold the layers together well. A 2:1 ratio of cream to milk, as used in this recipe, creates a silky, cohesive sauce that thickens beautifully during baking. Heavy cream ensures a luxurious mouthfeel, while a bit of whole milk lightens the dish enough to keep it from being overwhelmingly rich. This ratio also allows the cheese to incorporate smoothly into the sauce without curdling or separating.

Serving Suggestions and Garnishes

This gratin is indulgent on its own, but serving it with the right accompaniments elevates the entire meal. It pairs wonderfully with a crisp green salad dressed in a light vinaigrette to contrast its creamy richness. Roasted or grilled vegetables also complement the dish well, adding color and texture. For protein, serve alongside roast chicken, baked salmon, or seared tofu. Garnishes like freshly chopped parsley or chives add a pop of color and freshness. A sprinkle of crushed red pepper or a light dash of paprika can also enhance both flavor and presentation.

Low-Carb and Keto-Friendly Adaptations

This gratin is naturally low in carbs thanks to the use of kohlrabi, making it suitable for keto lifestyles. However, for stricter carbohydrate control, you can eliminate the milk entirely and use only heavy cream or even a dairy-free alternative like coconut cream or almond milk (unsweetened and unflavored). Choose aged cheeses with zero carbs, like aged cheddar or Parmesan. You can also add cooked bacon or pancetta between the layers for extra fat and flavor while still keeping it keto-friendly. Monitoring the portion size will help maintain the right balance of macronutrients in your meal.

Storage and Reheating Tips

Cheesy Kohlrabi Gratin stores well and makes excellent leftovers. Once cooled, it can be refrigerated in an airtight container for up to 4 days. When reheating, cover the dish with foil and warm it in a 350°F (175°C) oven until heated through—this helps retain moisture and prevents the top from over-browning. For quicker reheating, microwave individual portions in 30-second intervals, but be aware that the texture may soften more than in the oven. The gratin can also be frozen for up to 2 months. To freeze, cool it completely, wrap tightly with plastic and foil, and label with the date. Thaw overnight in the fridge before reheating.

Make-Ahead and Meal Prep Ideas

This recipe is ideal for preparing ahead of time, especially for dinner parties or holiday meals. You can assemble the entire dish up to a day in advance and store it covered in the refrigerator until ready to bake. If doing so, allow the dish to come to room temperature for 20–30 minutes before baking to ensure even cooking. Alternatively, bake it fully, then reheat when needed—just keep the baking time slightly shorter initially to prevent overcooking during reheating. For meal prep, portion the gratin into individual containers for grab-and-go lunches or side dishes throughout the week.

Adding Protein for a Complete Meal

While delicious as a side dish, Cheesy Kohlrabi Gratin can be turned into a satisfying main by incorporating protein. For a vegetarian option, consider adding sautéed mushrooms, lentils, or white beans between the layers. For meat lovers, shredded rotisserie chicken, diced ham, or crumbled sausage can be folded in before baking. These additions bring balance to the creamy base and help transform the gratin into a full, hearty meal. Just make sure any added proteins are pre-cooked and seasoned to blend seamlessly with the flavors of the cheese and cream sauce.

Flavor Variations and Enhancements

This recipe serves as a base that welcomes creativity and variation. For added depth, include caramelized onions or leeks between the kohlrabi slices. Herbs like thyme, rosemary, or sage can be infused into the cream mixture to add aromatic notes. A pinch of cayenne or a dash of smoked paprika will provide a subtle heat and smoky flavor. For a rustic twist, mix in sautéed spinach or kale for color and nutrition. Swapping a portion of the kohlrabi with other root vegetables like turnips or rutabaga also adds complexity without increasing carbs dramatically.

Conclusion

Cheesy Kohlrabi Gratin is more than just a healthy alternative to a potato bake—it’s a versatile, flavorful, and deeply satisfying dish that caters to a wide range of dietary needs and preferences. Its creamy texture, layered with melty cheese and tender kohlrabi, delivers comfort food appeal while offering lower carbs and more nutrients. Whether you serve it as a holiday side, prep it ahead for the week, or customize it into a one-dish meal, this gratin proves that wholesome eating can be indulgent too. With endless variations and pairing possibilities, it’s a staple you’ll want to return to again and again.