Who knew celery could be this luxurious? Baked in a velvety Mornay sauce with a golden bread crumb topping, celery gratin is rich, creamy and totally unexpected.
This recipe for celery gratin will reintroduce you to the humble green vegetable you thought you knew. Normally relegated to a supporting role as an aromatic, or added for texture in soups and salads, celery takes center stage in this creamy, cheesy gratin casserole.
And like the perhaps more familiar au gratin potatoes, this dish transforms simple vegetables into a rich and luxurious dish with a velvety sauce, golden crust and unexpected flavor that’s both comforting and elegant. Braising the celery in a classic Mornay sauce mellows its sharpness and brings out its sweetness as it becomes deliciously tender. Until you try this recipe, you haven’t truly experienced the full potential of this background vegetable.
Celery Gratin Ingredients
- Butter
- All-purpose flour
- 2% milk
- Heavy whipping cream
- Swiss cheese
- Salt and pepper
- Ground nutmeg
- Celery ribs
- Celery leaves
- White bread
Directions
Step 1: Make the sauce

Preheat the oven to 375°F. In a large saucepan, melt 6 tablespoons of the butter over medium heat.

Stir in the flour until it forms a smooth paste. Gradually whisk in the milk and cream. Bring the sauce to a boil, whisking constantly.

Cook and stir the sauce until it is thickened, three to four minutes. Stir in the cheese.

Stir in the salt, pepper and nutmeg until the sauce is combined.
Step 2: Add the celery

Stir the celery and celery leaves into the sauce.

Transfer the mixture to a greased 13×9-inch baking dish.
Step 3: Make the topping

Tear the bread into pieces, and place the pieces in a food processor or blender.

Cover the food processor and pulse until crumbs form, then transfer the bread crumbs to a large bowl.

Melt the remaining 2 tablespoons of butter and drizzle it over the bread crumbs, tossing to coat. Sprinkle the crumbs evenly over the celery mixture.
Step 4: Bake the gratin

Bake the casserole, uncovered, until it’s bubbly and the topping is golden brown, 25 to 30 minutes. If desired, sprinkle it with additional celery leaves.

How to Store Celery Gratin
Allow any leftovers to cool, then store them in an airtight container in the refrigerator, where they’ll keep for up to four days. Reheat leftovers in the microwave or on the stovetop over low heat until they’re warmed through. Since the sauce will continue to thicken after refrigeration, adding a splash of water or milk will help restore its creamy consistency.
Celery Gratin Tips

What are some variations of this celery gratin recipe?
To mix things up, swap out the Swiss cheese for another kind of melting cheese, or combine it with another cheese (like Gruyere) to create a blend. If you want to change the flavor profile of the celery gratin, try using pecorino Romano and Parmesan.
What other vegetables could I add to celery gratin?
If you’d like to make this a more veggie-forward dish, check out some of our other gratin casserole recipes like butternut squash au gratin, cauliflower gratin and au gratin cabbage for inspiration.
Can you make celery grain ahead of time?
Yes! You’ll want to cook and cool the vegetables before assembling and refrigerating the dish. Then when it’s time to bake, add a few minutes to the cook time. Pair one of these make-ahead side dishes to go with it.
Ingredients
- 1/2 cup butter, divided
- 6 tablespoons all-purpose flour
- 1 cup 2% milk
- 1 cup heavy whipping cream
- 3/4 cup shredded Swiss cheese
- 1/2 teaspoon salt
- 1/2 teaspoon pepper
- Dash ground nutmeg
- 8 celery ribs, cut into 1-inch pieces
- 1/2 cup chopped celery leaves
- 6 slices white bread, crusts removed
Directions
- Preheat oven to 375°. In a large saucepan, melt 6 tablespoons butter over medium heat. Stir in flour until smooth; gradually whisk in milk and cream. Bring to a boil, stirring constantly; cook and stir until thickened, 3-4 minutes. Stir in cheese, salt, pepper and nutmeg until combined. Stir in celery and leaves; transfer to a greased 13x9-in. baking dish.
- Tear bread into pieces and place in a food processor or blender. Cover and pulse until crumbs form. Transfer to a large bowl. Melt remaining 2 tablespoons butter. Drizzle over bread crumbs; toss to coat. Sprinkle over celery mixture.
- Bake until bubbly and topping is golden brown, 25-30 minutes. If desired, sprinkle with additional celery leaves.