Best Baked Kohlrabi Gratin
This Baked Kohlrabi Gratin transforms humble kohlrabi into a creamy, cheesy, and irresistible dish. It features tender, slightly sweet kohlrabi in a rich cream sauce, topped with melted Gruyere and cheddar for a comforting and flavorful side dish or vegetarian main course.
Equipment
- Vegetable peeler
- Mandoline or sharp knife
- Cutting board
- Large saucepan
- Whisk
- Measuring cups and spoons
- 9x13 inch baking dish
- Baking sheet (optional, for roasting)
- Spatula or spoon
Ingredients
- 2 lbs kohlrabi, peeled and thinly sliced about 1/8 inch thick
- 4 tbsp butter
- 1 medium onion, chopped
- 2 cloves garlic, minced
- ¼ cup all-purpose flour
- 3 cups milk
- ½ tsp salt
- ¼ tsp black pepper
- ¼ tsp nutmeg optional, but highly recommended!
- 1 cup shredded Gruyere cheese or a blend of Gruyere and Parmesan
- ½ cup shredded cheddar cheese
- 2 tbsp breadcrumbs optional, for topping
- 1 tbsp olive oil if roasting kohlrabi
Instructions
- Preheat your oven to 375°F (190°C).
- Peel the kohlrabi using a vegetable peeler or a sharp knife.
- Using a mandoline or a very sharp knife, slice the kohlrabi into thin, even rounds, about 1/8 inch thick. Even slices ensure the kohlrabi cooks evenly.
- Optional: Toss the sliced kohlrabi with 1 tbsp olive oil, salt, and pepper. Spread in a single layer on a baking sheet and roast for 15-20 minutes, or until slightly softened. If you skip the roasting, you might need to parboil the kohlrabi for 5 minutes to soften them.
- Melt the butter in a large saucepan over medium heat.
- Add the chopped onion to the melted butter and cook until softened and translucent, about 5 minutes.
- Add the minced garlic and cook for another minute until fragrant.
- Whisk in the flour and cook for 1-2 minutes, stirring constantly. This creates a roux, which will thicken the sauce.
- Gradually whisk in the milk, a little at a time, making sure to incorporate each addition fully before adding more. This prevents lumps from forming.
- Bring the sauce to a simmer over medium heat, stirring constantly. Continue to simmer for 5-7 minutes, or until the sauce has thickened enough to coat the back of a spoon.
- Remove the saucepan from the heat and stir in the salt, pepper, and nutmeg. Taste and adjust seasonings as needed.
- Stir in 3/4 cup of the Gruyere (or Gruyere/Parmesan blend) and the cheddar cheese until melted and smooth. Reserve the remaining 1/4 cup of Gruyere for topping.
- In a 9x13 inch baking dish, layer half of the kohlrabi slices (roasted or parboiled) evenly across the bottom.
- Pour half of the cheese sauce over the kohlrabi. Spread the sauce evenly to ensure every slice is coated.
- Add the remaining kohlrabi slices in an even layer, followed by the remaining cheese sauce.
- Sprinkle the remaining 1/4 cup of Gruyere cheese evenly over the top of the gratin. If using, sprinkle breadcrumbs over the cheese for a crispy topping.
- Bake in the preheated oven for 25-30 minutes, or until the top is golden brown and bubbly. The cheese should be melted and slightly browned.
- Remove the gratin from the oven and let it rest for 10-15 minutes before serving. This allows the sauce to thicken slightly and makes it easier to slice.
- Serve the Baked Kohlrabi Gratin warm as a side dish or as a light vegetarian main course.
Notes
For an extra crispy topping, broil the gratin for the last 1-2 minutes of baking, watching carefully to prevent burning. You can also add a pinch of cayenne pepper to the cheese sauce for a touch of heat. Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven or microwave until warmed through.