Red Chile Braised Beef

Name: Red Chile Braised Beef
Ingredients: 3 1/2 pounds (1,5kg) beef chuck roast (cut into 3 to 4-inch (8-10cm) chunks); coarse or kosher salt; freshly-ground black pepper; 4 dried ancho chiles (stemmed and seeded); 4 dried New Mexico, pasilla, or Guajillo chiles (stemmed and seeded); 1 quart (1l) chicken stock; 3 tablespoons neutral-flavored vegetable oil (plus more, if necessary); 2 medium onions (peeled and thinly sliced); 4 cloves garlic (peeled and thinly sliced); 1 teaspoon ground cumin; 1/2 teaspoon ground coriander seeds; 1 tablespoon light brown sugar