Roasted Leg of Lamb in Pasilla-Black Olive Sauce - Rick Bayless

Ingredients

• 12 (about 4 ounces total) dried pasilla chiles, stemmed, seeded and torn into flat pieces
• 1 head garlic, broken apart, leaving the cloves unpeeled
• 1/8 teaspoon cumin, preferably freshly ground
• 1/2 teaspoon dried oregano, preferably Mexican
• 1/2 teaspoon whole black peppercorns, preferably freshly ground
• 2 cups pitted Kalamata black olives, divided use
• 4 tablespoons olive oil, divided use
• 1 cup fruity red wine
• 4 ounces piloncillo or 2/3 cup dark brown sugar
• 1 6 to 7 pound boneless leg of lamb
• Zest of two lemons