French Green Vegetable au Gratin Recipe

Vegetable Gratin. Diana Miller - Getty Images
  • 55 mins
  • Prep: 10 mins,
  • Cook: 45 mins
  • Yield: 1 gratin serves 8

Vegetable gratin is such a lovely, versatile dish. It makes a great side dish which works well with many meats and fish dishes. Then, eat a larger portion and you have a great main course, for a simple lunch or even a dinner, add crusty bread on the side and you aslo have a filling dish. 

The smallest hint of a secret ingredient, poultry seasoning, is nearly undetectable hidden in the cheese and green vegetable mixture, yet gives the dish a special complexity. If you are serving this dish for a vegetarian, then leave out the poultry stock. 

What You'll Need

  • 1 small onion, finely chopped
  • 1 tablespoon olive oil
  • 2 tablespoons all-purpose flour
  • 3/4 teaspoon salt
  • 1/4 teaspoon ground black pepper
  • 1/2 teaspoon poultry seasoning
  • 1 1/2 cups whole milk
  • 1 pound broccoli, chopped
  • 2 cups chopped leaf spinach
  • 1 pound zucchini, chopped
  • 1 1/2 cups shredded Cantal cheese (substitute cheddar)
  • 3 tablespoons butter, melted
  • 1 cup bread crumbs
  • 1/4 cup Parmesan cheese

How to Make It

How to make green vegetable au gratin:

Preheat the oven to 375F and butter a large gratin dish.

Gently sauté the onion in the olive oil for five minutes in a medium saucepan set over medium heat. Sprinkle the flour over the onions and continue sautéing the mixture for 30 seconds. Add the salt, pepper, poultry seasoning, and milk to the pan and stir constantly for 3 to 5 minutes until the sauce thickens.

Stir the prepared broccoli, spinach, zucchini, and cheese into the sauce, bring the mixture to just a simmer, and then turn it out into the buttered gratin dish. Stir together the melted butter, bread crumbs, and 1/4 cup Parmesan cheese, and sprinkle the bread crumbs over the gratin. Bake the broccoli gratin in the preheated oven for 30 to 40 minutes, until it is hot and bubbly, the vegetable are tender, and the bread crumbs have turned golden brown.

This green vegetable gratin recipe makes 4 to 6 side dish servings.

Alternatives to the Classic Vegetable Gratin

The versatility of this means you can switch out the vegetables to suit your taste, seasonality, or pocket book. This recipe relies on green vegetables, but there is no reason to add a few mushrooms, or top off with a couple of meaty tomato slices. 

The cheese in this classic recipe us Cantal. Cantal has a very distinctive flavour which works very well with the vegetables. You can switch out the cheese for your own preferences, goats cheese or a crumbly blue cheese also work well.