1 tablespoon sumac

1 tablespoon cinnamon

1 teaspoon kosher salt

1 teaspoon cumin

2 pounds (1 kilogram) second-cut brisket or strips of flanken on the bone

3 tablespoons canola oil, divided

2 medium onions, cut into half-moons

3 large carrots, sliced

3 sweet potatoes, cut into small cubes

1 cup prunes, pitted (I used Gefen)

8 cups broth, such as Manischewitz Beef Broth

2 cups Tuscanini Crushed Tomatoes

salt, to taste

pepper, to taste