Vegetable Gratin with brussels sprouts and leeks in a cheesy white sauce, and topped with breadcrumbs and more cheese, a delicious side dish for the festive season. It's a heart-warming Winter dish that makes the perfect accompaniment for any roast or roast alternative, and it goes down well with the whole family.
Summer might be the time for fresh salads and crunchy greens, but there are some seasonal veggies that are at their best in Winter, and make the best side dish for your Christmas dinner menu.
Brussels Sprouts are not just cute-looking, they are also delicious and nutritious. Well, on their own, they might not be that interesting, but when we cook them in more appealing dishes, they are absolutely delicious.
I always serve Pan-Fried Brussels Sprouts with Bacon and Parmesan for our Thanksgiving feast, and my Maple Roasted Brussel Sprouts with Bacon and Sweet Potatoes is another dish that goes wonderfully well with the festive roast.
Although similar to my Chicken and Brussel Sprout Casserole, since they both use bechamel sauce, this vegetable au gratin is purely vegetarian, and uses fresh seasonal Winter produce.
For the vegetables
- brussels sprouts - I used fresh, but if you use frozen, make sure they are thawed beforehand
- onion - I used regular onion, but shallots are also ok
- garlic - the more, the better
- butter and olive oil - for sauteeing the veggies
- breadcrumbs and cheddar cheese - for topping the gratin
For the bechamel sauce:
- milk - I prefer full-fat milk, as it's creamier and richer, but semi-skimmed also ok
- flour - plain flour for thickening the sauce
- cheddar cheese and parmesan
- dijon mustard - it gives a sharpness to the sauce
- ground black pepper
- butter - I prefer salted butter, but unsalted also ok
Step-by-step photos and instructions
- In a large pan set over a medium heat, melt the butter, add the peeled and chopped onion, and fry until translucent
- Add the chopped leeks, garlic and brussels sprouts cut into halves, and give everything a good stir
- Leave to cook for 5 minutes until the veggies begin to soften
- Add half a cup of water to the pan, place the lid on, and leave it to cook until the water is evaporated
- 5. To make the bechame sauce, start by melting the butter in a frying pan set over a medium heat
- 6. Add the flour and whisk well
- 7. Gradually pour the milk in, and continue to whisk until the sauce starts to thicken
- 8. add the parmesan cheese, half of the cheddar cheese, dijon mustard, and pepper and give everything a good stir
- 9. To assemble the dish, add the veggies to the sauce, and give everything a good stir to combine.
- 10. Transfer everything to an ovenproof dish, and top with breadcrumbs and cheese
- 11. Bake in the preheated oven at 200 degrees Celsius (390 Fahrenheit) for 20-25 minutes until golden and bubbling hot.
This veg au gratin is so satisfying and comforting, and surprisingly light given the rich sauce the veggies are smothered into. But you do get all the goodness of the green veggies too.
Although it works beautifully as a vegetarian side dish, you can also add any other leftover meat to it too - if you don't have leftovers, make sure the meat is cooked before adding it to the sauce and veggies.
Leftover ham, chicken, turkey, beef or ham would make a great addition to it, especially that around this time of the year, and in particular after big feasts, there are always leftovers.
Other gratin recipes
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- 400 g fresh Brussels Sprouts
- 2 leeks
- 1 onion
- 3 cloves of garlic
- ½ cup water
- 25 g butter
- 1 tablespoon olive oil
- ½ teaspoon salt
- ⅛ teaspoon black pepper
- 3 tablespoon breadcrumbs
- 3 tablespoon cheddar cheese
For the bechamel sauce
- 1 cup full-fat milk
- 1 tablespoon plain flour
- 25 g butter
- ¼ cup grated cheddar cheese
- 2 tablespoon grated parmesan
- ½ teaspoon dijon mustard
- ⅛ teaspoon ground black pepper
- Cut the brussels sprouts into half and remove the tough ends.
- Rinse the leeks well with plenty of cold water to remove any dirt that might hide and chop them.
- Peel and chop the onion and garlic cloves.
- In a large pan, heat up the oil and add the butter - allow it to melt.
- Add the chopped onion and fry until golden, then add the garlic, leeks and brussels sprouts and sautee for 5 minutes.
- Pour over the water, place a lid on the pan, and leave to cook until the water is evaporated and the veggies are tender.
- In a separate pan, make the bechamel sauce.
- Melt the butter, add the flour and whisk well to get a smooth paste.
- Pour over the milk, and continue to whisk until the sauce thickens.
- Add the cheeses, dijon mustard and seasoning and mix well to get a cheesy sauce.
- Pour the sauce over the veggies and mix well to combine.
- Transfer everything to an ovenproof dish and top with the breadcrumbs and remaining grated cheese.
- Bake in the preheated oven at 200 degrees Celsius (390 Fahrenheit) for 20-25 minutes until golden and bubbling hot.
- Although it works beautifully as a vegetarian side dish, you can also add any other leftover meat to it too - if you don't have leftovers, make sure the meat is cooked before adding it to the sauce and veggies.
- Leftover ham, chicken, turkey, beef or ham would make a great addition to it, especially that around this time of the year, and in particular after big feasts, there are always leftovers.