When I set out to learn about the five mother sauces (click here and here if you missed the first two parts) I was excited about all of them except one – bechamel. What’s to get excited about? I’ve made it a thousand times (mac & cheese is a lifelong love), so my initial thought was “how boring.”
My plan was to sort of slip it in on my way to more exciting parts of this series (bring on the classic tomate and espagnole sauces!). However, despite my dead-beat approach to making bechamel, I did do my research and – lo and behold – I learned some things! And I used the bechamel sauce to make a rich and comforting roasted cauliflower gratin.

How to Make a Classic Bechamel Sauce
A holiday table or other celebration meal is not complete without a gratin, which is just a dish – in this roasted cauliflower – that is baked with a sauce and cheese or breadcrumbs on top. And so for this roasted cauliflower gratin, we start with a classic bechamel sauce that, up until now, I thought was just a simple combination of milk, flour, and butter.
So, I was surprised to learn that a lot of bechamel recipes call for an onion that you simmer in the butter, flour, milk mixture. I’ve never done that before and you might think it makes it all onion-y weird, but it doesn’t and the sauce ends up with just a subtle hint of onion. Oh, and I also learned that you should stick one itty-bitty clove into the onion so that the sauce gets infused with just a hint of clove – you can’t even tell it’s there. It adds a certain je ne sais quoi this whole clove business.

I learned I’ve been making bechamel wrong my whole life. Or I should say, I’ve been way too loosey- goosey with my bechamel up until now. I never paid much attention to the ratio of butter/flour/milk preferring to instead fly to by the seat of my pants. I also learned you have to take your time (I’ve always rushed through the process before) and, by the way, that time investment is so worth it – the resulting sauce was so creamy and had the most amazing consistency. Like, “Can I just drink that straight from the saucepan” amazing.
Let’s break it down… first, you melt the butter. I wanted my sauce very white (hence its nickname ‘white sauce’) so I melted the butter over pretty low heat before adding the flour to make the roux (lesson learned after making veloute sauce). After I poured the hot milk in I was quite pleased with the color – it was as white as newly fallen snow. I let it simmer and reduce until it was thick enough to coat a spoon. I had only a few little lumps that managed to adhere themselves to the spoon, as you can see, but it looks pretty good, right?

How to Make a Roasted Cauliflower Gratin
Now that I had my basic bechamel it was time to turn it into a sauce for the cauliflower gratin. To do this, I just added some shredded cheddar cheese to turn it into a rich and decadent cheese sauce.

While I was making the sauce I roasted cauliflower florets. From there I gently folded in some cauliflower florets that I roasted in the oven for about 30 minutes at 425 degrees. All of it went into a baking dish with some more cheese on top and I stuck it under the broiler until the gratin was bubbly hot.

This roasted cauliflower gratin can easily stretch to serve six – this is some serious creamy, cheesy comfort food best served as celebration food – you know, it’s a dish that’s so rich a lot goes a long way, so it’s best served for special occasions. Maybe for a holiday dinner? It’d go great alongside a nice slice of ham or turkey.
So this wraps up sauce #2 in my series and all I have to say is: Bechamel, I will never take you for granted again. I promise to use proper ratios, take the time to whisk, stir, and reduce each and every time I make you again. I realize now what a gift you are. You are so not boring.
More Decadent Side Dishes
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Roasted Cauliflower Gratin
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Total Time: 60 minutes
- Yield: 6 servings 1x
Description
Creamy, cheesy roasted cauliflower gratin.
Ingredients
- 2 tablespoons unsalted butter
- 1/3 cup all-purpose flour
- 21/2 cups whole milk
- 1/4 onion
- 1 clove
- 1 head of cauliflower, broken down into 2-inch florets
- 1 head of garlic
- 2 tablespoons olive oil, plus 1 teaspoon
- 2 cups cheddar cheese, grated
- 1/2 teaspoon kosher salt
- 1/4 teaspoon pepper
Instructions
- Preheat oven to 425°F. Toss the cauliflower florets with 2 tablespoons of olive oil and a couple pinches of salt and pepper. Spread the florets evenly on a baking sheet. Cut just the top off the head of garlic (enough to expose the cloves), drizzle 1 teaspoon of olive oil over the top and then wrap the garlic in tin foil. Place it on the sheet pan with the cauliflower. Roast the garlic and cauliflower for about 30 minutes, just until the cauliflower is tender and nicely browned in places.
- While the cauliflower is roasting, prepare the bechamel sauce. First, heat the milk in a saucepan until it just starts to simmer. While the milk is heating, in another saucepan melt the butter over low heat until frothy. Sprinkle in the flour and stir until it forms a paste. Slowly pour in the hot milk, whisking continuously to ensure no lumps form and the roux fully incorporates into the milk. Raise the heat to bring the pot to a simmer.
- Stick the single clove into the onion and add both to the milk mixture. Let the mixture simmer and reduce for about 20 minutes or so, or until it has reduced enough to coat the back of a spoon. You will need to stir frequently to ensure the bechamel does not burn at the bottom of the pan. Once reduced remove the onion and clove. You can strain the sauce to remove any lumps (or not, it’s up to you).
- When the garlic is roasted, squeeze out the cloves and mash with a fork. Add the garlic to the sauce and stir to combine. Stir in 1 1/2 cups of the grated cheese until it’s melted into the sauce. At this point taste for seasoning and add in some salt and pepper (I added 1/2 teaspoon of salt and 1/4 teaspoon of pepper, but season to your taste).
- Gently fold the roasted garlic into the sauce. Pour the mixture into an 8 x 8 baking dish, top with the remaining cheese and set it under the broiler until the cheese melts and starts to brown a bit on top. Remove from the oven and serve.
Notes
You can roast the cauliflower ahead of time following the instructions and keep it in the refrigerator for up to a day. Instead of placing the baking dish under the broiler, preheat the oven to 350 degrees and bake the dish for 20 to 30 minutes or until it’s bubbling and hot.
- Category: Side Dish
- Method: Bake
- Cuisine: American
Nutrition
- Serving Size: 1/6 of recipe
- Calories: 342
- Sugar: 6.3g
- Sodium: 498.7mg
- Fat: 25.4g
- Saturated Fat: 12.2g
- Unsaturated Fat: 10.8g
- Trans Fat: 0.3g
- Carbohydrates: 16g
- Fiber: 1.3g
- Protein: 13.9g
- Cholesterol: 57.6mg
Keywords: cauliflower gratin, cauliflower side dish recipe
The nutrition information in this recipe is an estimate only and was calculated using Nutrifox, an online nutrition calculator.
Leslie says
Hi, just a quick tip. I use a whisk to stir my sauce, as a result I don’t get lumps. You also need to cook the roux for 1 minute to avoid the grainy flour texture.
Colleen says
Five stars out of five for sure!
★★★★★
Colleen says
I just made this for Canadian Thanksgivig and it was incredible! Thank you! The onion and roasted garlic definitely took this to the next level of flavour. This is a keeper.
April says
I’m so glad you enjoyed it – Happy Canadian Thanksgiving 🙂
Brian Jones says
I am a sucker for cauliflower any which way it comes, but a nice cheese sauce is always a winner… Sounds delicious.
★★★★★
Whitney @ That Square Plate says
Thanks for sharing your tips about Beschamel sauce! The cauliflower gratin is a brilliant idea, and looks so mouthwatering! I love finding new recipes for cauliflower! Will have to try soon 🙂
★★★★★
Diane says
Wow! Nice lesson in bechamel sauce. I learned a few things here. The clove onion thing is totally new to me. Looks like I better make this recipe. Cheese, cauliflower and white sauce….great idea!
Rosemary @anitalianinmykitchen says
Looks delicious Apri, lots of cheese and creamy sauce is perfect for me.
Chrissie (thebusybaker.ca) says
This looks so delicious! And cauliflower is my fave!! 🙂
Tracy @ Served from Scratch says
Yum! This looks so delicious!!
Renee says
Anything with a cheesy cream sauce is delicious! Perfect comfort food!
Tina Marie says
I’ve never thought about adding the clove to the onion, genius! This looks so good!
★★★★★
Kelley @ Chef Savvy says
This looks amazing!! Love this series! Bechamel sauce is one of my favorites!
Denise | Sweet Peas & Saffron says
Great tips! I don’t make white sauce very often, but I too am pretty loosy-goosey! I will have to try the onion and clove trick!
Maya @ Treats and Eats says
I’m loving this series April! Turns out I’ve been making my bechamel a little too loosey goosey too- next time I’ll try it the proper way 🙂