Step 1Heat the oven to 500 degrees.
Step 2In a large bowl, toss the cauliflower with the olive oil to coat it well. Season with ½ teaspoon salt and several grinds of pepper, or to taste.
Step 3Heat a large skillet over high heat for 1 minute. Transfer the cauliflower to the skillet and cook, stirring only once or twice, for about 5 minutes, until golden-brown in a few places. Place the skillet in the oven and roast the cauliflower until brown in a few more places, another 5 minutes or so. Stir the cauliflower around in the skillet, then roast until just tender, 3 to 5 more minutes.
Step 4Remove from the oven and mix in the dill, vinegar and another pinch of salt. Taste a piece of cauliflower and add more vinegar and salt if needed. Serve hot or warm.