Cheesy & Creamy Brussels Sprouts Gratin (2024)

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This Cheesy & Creamy Brussels Sprouts Gratin is easy to make without the need for a béchamel sauce. Shredded brussels are gently cooked in butter with finely cut leeks then smothered with a rich and creamy cheese sauce. Grilled until golden and bubbling.

Once I made the smart decision to combine two of our traditional Christmas side dishes into one there was no looking back and I am flabbergasted that I have never done it before.

A Cheesy Brussels Sprouts Gratin is a staple for our festive table but the addition of shredded leeks which was usually our Spring take on the dish is such a revelation.

I’m sure you have a few brussels sprouts hold outs in the family but combined with buttered leeks in this rich creamy cheese sauce this dish will definitely encourage a few converts.

Why are these Cheesy and Creamy Brussels Sprouts such a brilliant side dish?

• Brussels sprouts and leeks are a vegetable marriage to last the ages.
• It’s a brussels sprout dish to convert the most adamant haters.
• It only take 25 minutes and is completely foolproof. No lumpy sauces here.
• You don’t need to make a béchamel sauce. Using cornflour is an easy way to make a cheese sauce which also makes it gluten-free.
• The perfect side dish which is delicious enough to be the main event for the vegetarians at the table.
• The cheese sauce is easy to make, rich with both mature cheddar cheese and cream cheese.
• Full of flavour thanks to smart seasoning.
• Honey dijon mustard. It adds incredible depth to the sauce.
• That final grilling means crunchy golden breadcrumbs and bubbling cheese – a tempting sight to add to the table.
• Easy to make-ahead or freeze.

What ingredients do you need for this Brussels Sprout Gratin?

• Brussels Sprouts - wash, trim the stalk and peel off any grubby layers before shredding.
• Leeks -wash, trim the ends and slice into thin coins to prepare.
• Butter -use unsalted so you can control the salt content.
• Whole Milk -using whole milk means the sauce is very creamy.
• Cornflour - makes the sauce lovely thick and smooth.
• Mature Cheddar Cheese -I love a sharp mature cheddar but you can sub for any melting cheese you fancy. Red leicester or gruyere are also lovely choices.
• Cream Cheese – I always use Philadelphia. It adds lovely richness to the sauce
• Honey Dijon Mustard – the sweetness of this mustard makes all the difference.
• Seasoning - onion granules, garlic powder, salt and pepper add lovely depth.
• Breadcrumbs - I use gluten-free breadcrumbs but you can use any.

How do you make Cheesy and Creamy Brussels Sprouts Gratin?

1. Cook the shredded Brussels and leeks in butter on a gentle heat for 15 minutes. Remove from the heat whilst you prepare the sauce.
2. Whisk the cornflour with the milk in a saucepan, then turn on the heat and whisk until bubbling and thick.
3. Add the cheddar, cream cheese, mustard and seasoning and stir until the sauce is thick and smooth.
4. Pour the sauce over the vegetables and mix until thoroughly combined.
5. Transfer the cheesy sprouts and leeks to an oven-to-table dish and sprinkle over the breadcrumbs and extra cheese.
6. Grill until golden and bubbling.

Pro Tips

• Peel off the outer layer of the Brussels and trim off the stalks to prepare.
• Shred the brussels and leeks as thin as you can for beautiful ribbony vegetables.
• You want the Brussels and leeks to be wilted in the butter but just turning golden at the edges.
• Swap out mature cheddar cheese for red leicester for a beautiful festive colour.
• If you can’t get hold of honey dijon mustard then regular dijon will do.

Recommended Equipment to make Cheesy Brussel Sprout and Leek Gratin

• Microplane Course Cheese Grater - It grates quickly and is so easy to wield.
• Flexi Whisk - In a similar vein I have a lot of different whisks but my favourite for sauces is a flexi whisk which gets into all the nooks and crannies of the saucepan meaning you get no unnecessary lumps.
• Oven-to-Table Pan - I wouldn't necessarily but for our weekly Sunday lunches you can bet I make and serve my gratins in my favourite cast iron pan. It's large enough that the pan can accommodate one-pan meals and small enough that it can fit into most ovens. Plus it looks pretty good on the table as part of a homestyle meal.

Make Ahead – This dish is so easy to prepare in advance. I usually get it to the stage before the final grill. Keep in an airtight container in the fridge for up to 3 days. Transfer the gratin to an oven-to-table dish and sprinkle over the breadcrumbs and extra cheese.

However, at this point heat the dish in the oven instead of the grill to ensure the dish is piping hot. Cook at 180°C for 20 minutes until golden and bubbling.

Freeze – You can freeze any leftovers no problem. However, you can also make the dish ahead of time as above. But instead of storing in the fridge you can freeze for up to 2 months. Defrost completely before cooking in the oven.

Variations of Cheesy & Creamy Brussels Sprouts Gratin

• Add cooked and chopped streaky bacon into the gratin before the final grill.
• Sub in some blue cheese into the sauce for a lovely complex dish.
• Include shredded kale into the proceedings.

Try these recipes if you are looking for more delicious side dishes

Gluten-Free Cauliflower Cheese
Carrot and Swede Mash
Braised Red Cabbage
Cream Baked Roast Potatoes
Chestnut and Sage Stuffing
Gluten-Free Yorkshire Puddings
Gluten-Free Gravy

If you make Cheesy & Creamy Brussels Sprouts Gratinthen please leave a comment below and give the recipe a rating which will help others find the recipe on Google. If you then go on to use this recipe as a launch pad for your own culinary creation then I’d also love it if you’d share it and tag me on Instagram. It is so lovely for me to see your versions and variations of my recipes.

This post was updated in October 2020 to give it extra sparkle but the recipe remains the same.