Roasting a whole head of cauliflower is a transformative experience, both for the cook and the cauliflower. At first you might be befuddled as to why anyone might want to cook an entire head of cauliflower whole, but as you pull the burnished heads of tender, aromatic cauliflower from the oven, you start to understand.
The resulting cauliflower — slathered in an herby butter and served with a rich onion gravy — goes from firm and toothsome to lusciously tender with a crackling, flavorful crust. It's super easy to prepare, but looks so impressive.
Why Roast Cauliflower Whole?
There are many reasons to roast a large vegetable whole, but flavor is chief among them. Cauliflower's inherent earthy sweetness become more pronounced as the moisture inside it is drawn out. Of course, whole roasting eliminates a ton of prep time and also leads to a very impressive vegetarian centerpiece on your table too.
For Your Information
- This recipe calls for two heads of cauliflower in the three-pound range and will feed six to eight as a side.
- The cauliflowers roast for an hour-and-a-half total, covered for the initial 30 minutes so that they steam slightly before roasting.
Step-by-Step Cauliflower Transformation
- Core the cauliflower. The stalk or core of the cauliflower is arguably the thickest part of the cauliflower, and removing it before roasting does the following things: it allows seasoning to reach the inner pieces of cauliflower, makes it easier to slice later, and significantly trims the cook time.
- Dress in herb butter. Much like a roasted chicken or turkey, cauliflower loves being slathered in a rich, flavorful butter. Room-temperature butter is best and while a spatula will work, I find it's easiest to work the butter into the cauliflower with clean hands.
- Steam in the oven before roasting. If you just plainly roast a cauliflower, it will dry out in the hot oven before become tender. Instead, cover the cauliflower for the first 30 minutes of roasting with water or broth in the pan, and it will be well on its way to perfection before it starts to crisp and brown.
- Roast until tender. After steaming for 30 minutes, roast the cauliflower uncovered for another hour. The cauliflower will go from pale to golden and finally very deep browned. Much of the liquid in the pan will evaporate, leaving you with soft onions and garlic for turning into gravy.
Serving Your Whole Cauliflower
Once roasted, you can move your roasted cauliflower to a serving platter and use the pan drippings to make a rich brown butter and onion gravy to cover the cauliflower heads. We typically cut the roasted cauliflower into thick wedges for serving under the gravy. Each bite is so luxuriously tender, you'll only need a fork to sink into the wedge to enjoy.
How To Make a Whole Roasted Cauliflower
What You Need
For the cauliflower:
1 large onion, thinly sliced
4 cloves garlic, peeled and smashed
2 large heads cauliflower (about 3 pounds each)
1 teaspoon kosher salt
8 tablespoons (4 ounces) unsalted butter, at room temperature
1 teaspoon dried thyme
1 teaspoon dried sage
1 teaspoon dried rosemary
1 cup low-sodium vegetable broth
For the brown butter gravy:
4 tablespoons (2 ounces) unsalted butter
1/4 cup all-purpose flour
Pan drippings from above, including caramelized onions and garlic
2 cups low-sodium vegetable broth
Water, as needed
9x13-inch metal baking pan or roasting pan
- Heat the oven to 400°F and line a baking pan with onions and garlic. Arrange a rack in the middle of the oven and heat to 400°F. Place the onion and garlic in an even layer in a roasting pan or 9x13-inch metal baking pan.
- Core and season the cauliflower. Use a paring knife to cut the core out of each cauliflower: Flip the cauliflower over so the stalk is facing up. Insert the paring knife about 2 inches into the cauliflower, as close to the stalk as possible, and cut around the stalk. The goal is to leave the cauliflower intact while removing the stalk and creating a small bowl where it once was. Sprinkle the cauliflower all over with the salt, including the opening where the stalk was just removed.
- Make an herb butter. Place the butter, thyme, sage, and rosemary in a small mixing bowl and mix until well-combined.
- Coat the cauliflower with the herb butter. Using clean hands (or a spatula) cover the heads of cauliflower all over with the herb butter, paying particular attention to the top and sides of the head.
- Cover the roasting pan and bake for 30 minutes. Place the cauliflower heads, cored-side down, in the prepared pan on top of the onions. Add the broth and cover the whole pan with aluminum foil. Bake for 30 minutes so that the broth steams the cauliflower and softens the onions.
- Uncover and roast for another 60 minutes. Uncover and continue to roast the cauliflower until their tops are golden-brown, bordering on blackened and tender, about 60 minutes more.
- Cool the cauliflower and make the gravy. Remove the pan from the oven and transfer the cauliflower heads to a serving dish. Melt the butter for the gravy in a small saucepan over medium heat and cook until the butter browns, about 3 minutes. Add the flour and cook until dry. Add the drippings from the roasting pan, onions and all, as well as the broth. Cook until thickened, about 5 minutes. At this point, you can purée the gravy for a smooth sauce using an immersion blender, or serve as is. Add water and thin out if needed to the desired consistency.
Slice the cauliflower and serve. Slice the cauliflowers into thick wedges and serve with the gravy.
- Storage: Store leftovers in an airtight container for up to 4 days. Reheat slices over low heat in a skillet for added crispness.