Asparagus and Goat Cheese Frittata

INGREDIENTS

• 12 eggs
• 3 Tbs. finely chopped fresh chives
• 1/4 tsp. finely chopped fresh tarragon
• 2 Tbs. finely chopped fresh chervil
• 2 oz. prosciutto, cut into 1/4-inch strips
• 1/2 tsp. salt, plus more, to taste
• Freshly ground pepper, to taste
• 6 oz. goat cheese, crumbled
• 2 lb. asparagus, tough ends trimmed, spears steamed until just tender
• and cooled
• 3 Tbs. unsalted butter
• 1 leek, thinly sliced and rinsed well