Braised Lamb Tacos

Name: Braised Lamb Tacos
Ingredients: 1 tablespoon cumin seeds; 1 tablespoon coriander seeds; 1 cup sherry vinegar; 1 cup extra-virgin olive oil; 10 cloves garlic, smashed; 1/4 teaspoon red pepper flakes; 1 cinnamon stick; 2 tablespoons packed light brown sugar; 2 teaspoons ancho chile powder; 1 16-ounce can crushed tomatoes; 1 5-pound bone-in leg of lamb, cross-cut into 5 to 6 pieces (ask your butcher to do this); Kosher salt and freshly ground pepper; 3 tablespoons canola oil; 2 12-ounce bottles lager beer (I like Great Lakes Dortmunder Gold); 1 jalapeno pepper, chopped; Corn tortillas, warmed, for serving; Cilantro, for topping