Step 1

Preheat a gas grill to medium-high or prepare a medium-hot fire in a charcoal grill.

Step 2

Rinse the radicchio quarters and pat them dry. Brush the radicchio quarters with oil and place the heads on the grill rack. Cover, and cook, turning as necessary, until grill-marked but still crunchy in the middle, 2 to 3 minutes per side. Transfer to a plate.

Step 3

In a small bowl, whisk together the 1/4 cup olive oil, the vinegars, mustard, salt, and pepper. Divide the grilled quarters among plates and crumble the Gorgonzola over the top. Drizzle with the balsamic vinaigrette and serve pronto.