Trim fat from lamb. Cut lamb into 3 x 1/4-inch strips. Place a skillet over medium-high heat until hot. Add lamb; cook 4 minutes or until browned. Add jalapeño, oregano, chili powder, salt, and garlic, and saute 1 minute. Stir in tomato paste, and sauté 2 minutes. Stir in water, raisins, and cocoa; bring to a boil. Reduce heat; simmer 20 minutes. Stir in olives, cilantro, and juice.
Warm tortillas according to package directions. Spoon about 1/2 cup lamb mixture down center of each tortilla; roll up.