Chocolate Lamb Chili

2 tablespoons chili powder
1 tablespoon ground coriander
2 teaspoons ground cumin
1 teaspoon dried oregano
1 teaspoon dried thyme
1/2 teaspoon ground cardamom
2 tablespoons flour
3 pounds boneless leg of lamb, trimmed of visible fat and silver skin, then cut into 1/2-inch pieces
Sea salt
Freshly ground black pepper
3 tablespoons vegetable oil
2 large yellow onions, diced
1 medium eggplant, peeled, then cut into 1/2-inch squares
2 cloves garlic, minced
2 chipotles in adobo, finely chopped, plus 1 tablespoon adobo
1 1/2 cups no-salt-added beef broth
28 ounces canned, no-salt-added diced tomatoes plus their juices, preferably not fire-roasted
30 ounces to 31 ounces canned, no-salt-added white kidney beans or cannellini (may substitute navy beans)
2 ounces bittersweet chocolate, finely chopped
3 tablespoons finely chopped cilantro

Directions

Step 1
Combine the chili powder, ground coriander, ground cumin, dried oregano, dried thyme, ground cardamom and flour in a small bowl.
Step 2
Season the lamb with salt and pepper to taste.
Step 3
Heat the oil in a large skillet over medium-high heat. Working in three or four batches, brown the lamb pieces, transferring them to the slow-cooker as they are done.
Step 4
Add the onions and eggplant to the skillet, stirring to coat. Cook for about 4 minutes, until lightly browned, then add the garlic and chipotles; cook for about 30 seconds, then stir in the adobo and the chili powder-spice mixture. Cook for about 1 minute, then stir in the broth and tomatoes. Cook, stirring a few times, for about 5 minutes.
Step 5
Transfer to the slow-cooker. Cover and cook for 4 to 5 hours on HIGH (or 8 to 9 hours on LOW). The lamb should be falling apart. Stir in the beans; cover and cook just until they have warmed through.
Step 6
Just before serving, add the chocolate and cilantro, stirring until the chocolate melts.