1 1/4 pounds fresh asparagus (trimmed, peeled, and cut into 2-inch lengths)
1/4 cup unsalted butter
1 cup thinly sliced leeks (white and light green parts only)
1 cup diced, peeled potato (1/4-inch dice)
4 cups chicken stock
1 teaspoon salt (or to taste)
  Freshly ground black pepper (or to taste)