To make the grilled leeks, begin by trimming the leeks: cut off the roots and the tough dark green tops.
Make a light lengthwise slit to remove two additional outer layers, leaving approximately 650 g (1.4 lbs) of tender leek hearts.
Rinse the cleaned leeks thoroughly under cold running water and set them aside.
Fill a large pot with water and bring it to a boil. As soon as it boils, add salt and submerge the leeks. Cook over medium heat for about 15 minutes.
Drain the leeks and transfer them to a colander to drain off any excess water.
Heat a non-stick grill pan and grill the leeks for about 10 minutes, turning them occasionally until tender and evenly marked.
Once well-grilled, arrange the leeks onto a serving platter.
Thoroughly wash the fresh herbs and finely chop them on a cutting board.
In a small bowl, combine the extra virgin olive oil, salt, black pepper, and the chopped herbs. Whisk with a fork to emulsify the dressing.
Drizzle the grilled leeks first with the herb-infused oil, followed by the balsamic vinegar. Allow them to marinate in the refrigerator for at least 30 minutes before serving.