As healthy and rice-able as cauliflower is, it can also be rich and decadent. This Cauliflower Mustard Au Gratin definitely leans toward the latter with a rich, slightly smoky mornay sauce spiked with whole grain dijon mustard for a little tang. #doesntsuck.
This classic au gratin starts with a béchamel, enhanced with a few pantry staples to amp up the flavor.
Tangy cheddar and smoked gouda transform the béchamel to a gloriously creamy, lush sauce.
Steam the cauliflower until it’s just tender and transfer to a baking dish. Pour the cheese sauce over the cauliflower. Sprinkle with cheddar cheese and breadcrumbs to develop a good crust and bake.
Those golden, crispy crumbs on top can barely mask the cheesy-gooey interior of this casserole.
When you tuck your spoon into the mix, and get a whiff of that rich mornay you’ll get a sense of the treat that you’re in for — tender cauliflower in a creamy, cheesy, tangy sauce that oozes across the plate. This is a great side dish to roast meats or pan sautéed seafood — and if you’re looking for Thanksgiving inspiration, this is it.
Cauliflower Au Gratin
A rich, indulgent gratin with a cheesy, mustard-spiked mornay sauce that's perfect for entertaining and the holidays.
- 1 head cauliflower
- 2 1/2 tablespoons unsalted butter
- 2 1/2 tablespoons all purpose flour
- 1/4 teaspoon nutmeg
- 3/4 teaspoon dry mustard
- pinch cayenne pepper
- 1 teaspoon kosher salt
- 1/2 teaspoon black pepper
- 2 cups milk
- 1 cup cheddar cheese grated, divided
- 1/2 cup smoked gouda grated
- 2 teaspoons whole grain dijon mustard
- 1/4 cup panko or breadcrumbs
Preheat the oven to 375°. Spray a small casserole dish with vegetable spray and set aside.
Trim the end from the cauliflower and cut it vertically into 1" slabs. Trim the florets from the stem and then cut the stem into bite sized pieces. Add about 1/2" water to a large pot and fit it with a steamer basket. Bring the water to a boil and place the cauliflower into the basket. Steam for about 10 minutes or until tender. Set aside.
In a medium saucepan, heat the butter over medium high heat. When butter is melted and bubbly, whisk in the flour, nutmeg, dry mustard, cayenne pepper, kosher salt and black pepper. Stir until the butter and dry ingredients form a paste or roux. Slowly add the milk, whisking constantly. Cook, stirring and scraping the sides and edges until the milk mixture thickens and comes to a low boil. Cook for one minute and remove from heat.
Add 3/4 cup cheddar cheese and 1/2 cup gouda, stir until cheese is melted. Stir in the whole grain dijon and set aside.
Spoon 1/4 cup cheese sauce into the bottom of the casserole and spread evenly. Use a slotted spoon to transfer the cauliflower to the casserole and arrange in an even layer. Top with cheese sauce. Sprinkle on the remaining cheddar cheese and bread crumbs.
Bake for 18-20 minutes until bubbly, then turn on the broiler to high and cook for 1-2 more minutes or until breadcrumbs are nicely browned. Remove from oven and rest for 5-10 minutes before serving.
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