Preheat your oven to 375 degrees. Cut off the outer cauliflower leaves. Trim a bit of the stalk, enough so that it’s fairly flat and the cauliflower can rest on it.  

Fill a large pot with enough water so that you can submerge about ¾ of the cauliflower. Once the water is boiling, carefully lower the cauliflower into the water, stem side up. Return the water to a boil and cook for 5 minutes. Remove the cauliflower and place it stem side up in a colander to drain the excess water.  

Place cauliflower, floret side up, on a parchment-lined roasting pan. Mix softened butter and olive oil together and brush on the whole cauliflower, sprinkle with a bit of flaky sea salt. Roast for 1 – 1 ½ hours, occasionally basting with more of the butter/oil mixture that’s collected in the pan. You want it cooked but not so soft that it all breaks apart into pieces.  

Remove from the oven, cool for a few minutes, and then cut into wedges. Top with the desired topping.