1 loaf Italian or French rustic bread, cut into 1 1/2-inch cubes, about 8 cups total of bread cubes
1 pound asparagus spears, woody ends removed, spears cut into 3/4-inch pieces
Salt (for blanching water)
1 medium bowl of ice water
2 Tbsp softened butter (for buttering the dish)
6-ounces ham, cut into 1/4-inch cubes, about 2 cups
4-ounces Gruyere cheese, grated, about 1 cup, packed
4 eggs
1 1/4 cups cream
1 3/4 cups milk
1 teaspoon salt
1 teaspoon dried tarragon (or thyme)
1/4 teaspoon ground black pepper