1
Adjust rack to middle position and preheat oven to 450 degrees. Wash and dry all produce.
Dice potatoes into ½-inch pieces. Halve, peel, and mince shallot. Zest and quarter lemon. Trim and discard woody bottom ends from asparagus. Place peppercorns in a zip-close bag; crush with a heavy-bottomed pan or rolling pin until coarsely ground.