1Make a simple dressing with mustard, vinegar, honey, garlic, and olive oil.
2Brush the dressing on a whole head of cauliflower.
3Roast the cauliflower until it is pretty soft.
4Mix parsley and feta together.
5Once the cauliflower is soft, rub it with pure mustard for a bright tang.
6Take the feta and parsley mixture and pat it on the cauliflower, separating the florets and getting it in the little crevices for different textures of feta.
7Finish roasting until the feta is nice and melty.
8Take it out of the oven and serve with the remaining sauce.