Preparation

Make the vinaigrette

Put half of the corn kernels in a medium bowl, and mash them with a fork to release some of their milk. Add the oil, vinegar, citrus juice, syrup, salt, and several grinds of pepper. Whisk well. Stir in the remaining corn kernels and chives.

Make the potatoes

• Prepare a medium (350°F to 400°F) gas or charcoal grill fire. In a large bowl, toss the potatoes, shallots, oil, herbs, 1 tsp. salt, and a few grinds of pepper.
• Measure out three sheets of aluminum foil, each about 20 inches long. Overlap two pieces in a cross pattern. Mound the potato mixture in the middle of the cross, and spread it out just enough to form a square of even thickness. Fold each piece of foil in and over the potatoes to wrap the package, and then wrap the third piece of foil around the package for a good seal.
• Put the package directly on the grill grate. Place the lemon halves cut side down on the grate. Cover the grill. Cook the potato package for 20 minutes (you’ll hear sizzling). During this time, raise the lid from time to time to turn the lemon halves. Remove them from the grill when they’re charred and appear juicy, about 15 minutes. After 20 minutes, turn over the potato packet, and cook for 20 to 25 minutes more. Remove the package from the grill, and open it carefully with tongs. (It will release hot steam.) The potatoes should be tender when pierced with a fork and nicely browned in places. If they aren’t tender, rewrap, and cook for 5 more minutes.
• Arrange the arugula on a small platter or four individual plates, and portion the potatoes and shallots over the greens. Zest one of the charred lemon halves. Finely chop the zest and sprinkle over the arugula. Squeeze the juice of the lemon halves over the salad. Season to taste with salt, and spoon 3 to 4 Tbs. of the vinaigrette over the potatoes and salad.