The secret to grilling greens is to allow them to marinate in the olive oil, salt, and pepper mixture for up to an hour. This applies, as well, to greens you will be searing. Cast-iron is best for searing, but a heavy stainless steel skillet will work, too.

1 or 2 heads radicchio (or curly endive)
olive oil, as needed
salt and pepper, to taste
lemon juice
chopped fresh parsley, or other herb

Grilling:
1. Cut the radicchio into quarters. Brush them with olive oil and season with salt and pepper. Or, put the quarters in a large bowl, drizzle with olive oil, add salt and pepper, and toss well. Allow to marinate for about an hour, or at least 15 minutes.

2. Put on grill, for about 5 minutes a side (this will depend on the heat of your fire), until the radicchio has softened and turned brownish. Remove from grill to a serving platter. Gently press the wedges to open the leaves. Drizzle with lemon juice and sprinkle with chopped parsley, or other herb.

Searing:
1. Prepare radicchio as for grilling, above. Brush a cast-iron skillet lightly with oil and set over a medium-high heat. When the oil is shimmering, and the skillet is very hot, add the radicchio and sear until the leaves begin to turn brown on the bottom, a couple of minutes. Flip over and cook the second side for another couple of minutes. Remove from heat and proceed as for grilled radicchio.