2 pounds large Yukon Gold or other yellow-fleshed potatoes
1/4 cup chopped mixed herbs such as parsley, chives, rosemary, and oregano
2 garlic cloves, smashed
1/3 cup extra-virgin olive oil
1 lemon wedge plus additional for serving
Prepare a gas grill for direct-heat cooking over medium-high heat; see Grilling Procedure .
Cut potatoes into 1/2-inch-thick slices and cook in a large pot of well-salted boiling water 10 minutes (potatoes will not be cooked through).
Meanwhile, stir together herbs, garlic, oil, 1/2 teaspoon salt, and 1/4 teaspoon pepper in a large shallow dish.
Drain potatoes well and transfer to herb oil, tossing gently to coat.
Transfer potatoes to grill, letting excess oil drip into dish (reserve oil in dish). Grill potatoes, covered, turning once or twice, until tender, about 5 minutes total. Return potatoes to dish and toss again with herb oil. Squeeze lemon wedge over potatoes. Season with salt and serve with additional lemon wedges.
Potatoes can be cooked in a hot grill pan 10 to 12 minutes.