Vegetable Au Gratin Recipe

Vegetable au Gratin is a classic baked dish made with tender mixed vegetables & mushrooms coated in a smooth white sauce and topped with a golden cheese layer. It’s simple food but feels both comforting and special. I often make it for weekend dinners or on days when I want something easy yet satisfying. If you enjoy mild, creamy vegetable dishes, this Veg au Gratin recipe is a lovely one to add to your repertoire.

My Take on Vegetable Au Gratin

Gratin is a French cooking technique where ingredients are baked with a layer of cheese, breadcrumbs or both until the top becomes golden and crisp. The word comes from “gratiner,” meaning to brown under heat.

Over the years, this style of cooking has travelled across cuisines, and today you’ll see many variations, from simple vegetable gratins to richer pasta-based ones.

The potato gratin, or “gratin dauphinois,” is probably the most well-known version globally. Thin slices of potatoes baked slowly in cream or béchamel with cheese on top. It’s a classic comfort dish in many countries.

Vegetable au Gratin is popular in India because it feels both continental and familiar. The vegetables stay tender and the white sauce brings everything together without feeling heavy.

What makes my Veg au Gratin a little different is how easy the cooking process is. I add all the vegetables to the pot at the same time, which keeps things straightforward.

For this gratin, I use a mix of vegetables that cook well together. I chop the potatoes and carrots into small cubes, roughly ½ to ¾ inch, so they soften nicely.

Baby corn goes in as slices, and the cauliflower is cut into small florets. French beans are chopped into ¾ to 1-inch pieces, and I add green peas straight in, fresh or frozen.

I also like adding mushrooms because they give a good depth of flavor. Bell pepper is optional, but you can add a little if you have it.

A well-made white sauce is the base of any good gratin. If the sauce is thin, the gratin won’t bake well and the texture will not hold. So take your time with this step.

You can also roast the vegetables instead of boiling or steaming them. Roasting gives a deeper flavor and works beautifully in a Vegetable au Gratin.

Cheese is another area where you can customise. Use a melty cheese like cheddar, mozzarella or a blend. You can grate two or three types together for more flavor.

I always recommend grating your own cheese because packaged shredded cheese often contains starch or anti-caking agents that affect the texture.

For the topping, breadcrumbs give a nice crisp finish. Panko breadcrumbs make it even lighter and crunchier. If you don’t have breadcrumbs, you can skip them. The Veg au Gratin still tastes very good with just cheese.

I first tasted Vegetable au Gratin when I was in my teens, at a multi-cuisine restaurant in Pune. I was with a group of friends and we ordered it almost randomly. All of us loved it.

The creamy vegetables and the melted cheese felt so comforting. That memory stayed with me and later I started making the dish at home. Even now, this Veg au Gratin recipe reminds me of that time.

More Creamy Dishes

• Mac and Cheese
• Baked Ziti
• White Sauce Pasta
• Veg Lasagna
• Creamed Spinach

How to Make Vegetable Au Gratin

Making Vegetable au Gratin is simple once you break it into three parts. First you prep and cook the vegetables, then you make a smooth white sauce, and finally you assemble everything and bake it until golden. The steps look long, but the process is easy and very doable for beginners.

Prep & Cook Veggies

1. Rinse all the vegetables well and chop them as follows:

• Potato: ¾ to 1 cup, cut into small cubes (about ½ to ¾ inch).
• Carrots: ⅓ cup, chopped into ½ to ¾ inch cubes.
• Baby corn: ⅓ cup, sliced into rounds.
• Cauliflower: 1 to 1.25 cups, cut into small florets.
• French beans: ¼ cup, chopped into ¾ to 1-inch pieces.
• Green peas: ½ cup, fresh or frozen.
• Button mushrooms: 1 cup, chopped or sliced.
• Bell pepper (optional): ¼ cup, chopped, optional

Set all the chopped vegetables aside.

2. In a pot, add 3 cups water and ¼ teaspoon salt. Bring to a boil on medium to medium-high heat.

3. Add all the chopped vegetables and mushrooms.

4. Cover pan with lid.

5. Simmer and cook on medium-low heat for 25 to 30 minutes or until the veggies are fork-tender but not mushy.

6. Drain using a mesh strainer. Save the vegetable stock for soups or lentils.

Make sure the veggies are completely drained. Any excess water can thin the sauce.

Make White Sauce

7. Keep a saucepan on low heat. Add 3 tablespoons butter.

8. When the butter melts, add 3 tablespoons whole wheat flour (or all-purpose flour).

9. Whisk immediately to form a smooth roux. Stir continuously until the mixture becomes pale golden and smells nutty.

10. Keep the stovetop heat to its lowest. Slowly pour 1.5 cups cold milk in a steady stream, whisking constantly so no lumps form.

11. Mix very well.

12. Continue cooking on low heat and stir frequently.

13. On a low heat, stirring often, simmer the sauce until it thickens and and coats the back of a spoon.

14. Turn off the heat and place the pan on the kitchen countertop. Add ⅓ teaspoon ground black pepper, ⅛ teaspoon grated nutmeg, salt as needed, and optionally 2 tablespoons grated cheddar.

15. Mix well. Let the sauce cool slightly.

16. The sauce thickens as it cools. The image below shows the consistency of the sauce after it has cooled slightly.

Assemble & Bake Veg Au Gratin

17. Once the sauce is warm or at room temperature, add in the cooked vegetables and mushrooms.

18. Gently fold or mix so the sauce coats everything evenly.

19. Grease a baking dish or a pie dish with 1 to 2 teaspoons softened butter. Preheat your oven for 15 minutes at 180°C (356°F).

20. Transfer the vegetable-white sauce mixture to the baking dish and level the top.

21. Add ½ cup grated cheddar (can also use a mix of cheddar or mozzarella). Sprinkle ⅓ cup breadcrumbs if you want a crisp top.

Sprinkle ½ teaspoon of mix dried herbs like oregano, parsley, basil etc on the cheese layer.

22. Place the baking dish in the preheated oven.

Tip: Turn on both the top and bottom heating elements. If you’re using a smaller oven, place the baking dish on the second-last rack for even browning.

23. Bake at 180°C (356°F) for 30 to 40 minutes or until the cheese melts and turns golden.

24. Let the baked Vegetable au Gratin rest for 5 minutes before serving. Serve hot or warm.

Serving Suggestions

Vegetable au Gratin is usually served as a standalone main dish in continental cuisine. It pairs well with warm Garlic Bread or soft dinner rolls.

A light soup on the side makes the meal more wholesome. You can also serve Veg Au Gratin with my Tomato Soup, Sweet Corn Soup or French Onion Soup.

A basic Green Salad or sautéed veggies also works well if you want something fresh on the side.

Storage

Keep any leftovers in an airtight container in the fridge for 1 to 2 days. The gratin thickens as it cools, so reheat it in an oven or air fryer for the best texture.

You can warm it on the stovetop too, but the sauce may loosen a bit. Avoid freezing because the white sauce can split after thawing.

Vegetable Prep Tips & Notes

• Vegetable Size: Chop the vegetables into small pieces so that they cook faster.
• Cooking Veggies: Sometimes the vegetable and water mixture may froth while cooking, so ensure to simmer on a medium-low heat.
• Moisture Control: After boiling, drain the vegetables very well. Excess water will thin the sauce and prevent the gratin from setting properly in the oven.
• Vegetable Selection: Use any mix of vegetables you enjoy. Just avoid tomatoes or acidic vegetables because they can cause the béchamel to split during baking.
• Roasting Option: For deeper flavor, roast the vegetables instead of boiling them. Roasted vegetables bring a mild caramelized taste and hold their texture better in the final Veg au Gratin dish.
• Steaming Veggies: Instead of cooking vegetables in water, you can also steam them in a steamer.

Sauce, Assembly & Baking Tips

• Cold Milk Helps: When making the white sauce, add cold milk to the roux. Cold milk prevents lumps and helps the sauce come together smoothly.
• Slow Thickening: Stir the sauce often as it heats so it doesn’t stick or scorch. Slow, even thickening gives the best texture.
• Right Consistency: The sauce should be thick enough to coat the back of a spoon before mixing in the vegetables. A thin sauce will make the gratin watery once baked.
• Cheese in the Sauce: You can turn the béchamel into a mornay sauce by adding freshly grated cheese. Avoid packaged shredded cheese because it contains starches that can make the sauce gritty.
• Heat Control: Keep the flame low to medium-low when cooking the sauce. High heat can thicken it too fast and create lumps.
• Cheese Layer: Use a melty cheese like cheddar, mozzarella or a blend of both. Mixing cheeses gives better flavor and melt.
• Breadcrumb Options: If you prefer a crisp top, sprinkle breadcrumbs or panko over the cheese. Panko gives a lighter crunch. The gratin also tastes good without breadcrumbs.
• Even Layering: Spread the vegetable–sauce mixture evenly in the baking dish so that the gratin cooks evenly from edge to center.
• Resting Time: Let the baked vegetable gratin rest for some minutes before serving. This helps the sauce settle and makes it easier to serve without breaking.
• Baking Heat: Maintain a steady temperature. If the top browns too quickly, cover loosely with aluminium foil so the inside continues cooking without over-browning the cheese.

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