Dinner: Grilled Beef Tenderloin with Potato Hobo Packs

Ingredients

2 tablespoons black peppercorns
1 1/2 tablespoons kosher salt
2 tablespoons olive oil
1 (2 1/2-lb) center-cut beef tenderloin roast, trimmed and tied
1 1/2 lb fingerling or baby Yukon Gold potatoes (about 16), halved lengthwise
1/2 lb pearl onions (about 16), blanched in boiling water 1 minute, drained, and peeled
12 garlic cloves
2 tablespoons minced fresh sage
1/4 cup extra-virgin olive oil
1/2 cup sour cream
6 bacon slices, cooked and crumbled
1/4 cup thinly sliced fresh chives
Special equipment: 12-inch-wide heavy-duty aluminum foil; a 22 1/2-inch kettle grill with a hinged top rack (if using charcoal); a large chimney starter (if using charcoal); long metal tongs; a 17- by 12 1/2- by 3 1/2-inch disposable aluminum roasting pan (if using charcoal); an instant-read thermometer

Instructions

Coarsely crack peppercorns (see cooks' note, below). Stir together pepper and salt in a small bowl, then add oil and stir until combined well. Rub spice mixture all over beef.
Tear off 8 (2-foot-long) sheets of heavy-duty foil and arrange in 2 stacks of 4. Divide potatoes, onions, garlic, and sage between stacks, arranging in 1 layer in center of foil, then drizzle each with 2 tablespoons oil and season with salt and pepper. Working with top sheet of foil, fold each side over potato mixture to enclose, then turn package a quarter turn and repeat folding and turning package with each piece of remaining foil. Make second hobo pack in same manner.