• 3 pounds beef chuck roast, cut into large chunks

• 2 tablespoons vegetable oil

• 1 large onion, roughly chopped

• 4 cloves garlic, minced

• 2 dried guajillo peppers, stemmed and seeded

• 2 dried ancho peppers, stemmed and seeded

• 1 tablespoon dried oregano

• 1 teaspoon ground cumin

• 1/2 teaspoon ground cinnamon