Pot Roast and Sweet Potatoes

Originally found here. 

Ingredients
1 ½ to 2 pounds boneless beef chuck roast
2 tablespoons oil
1 onion, thinly sliced
3 sweet potatoes, peeled and quartered
⅔ cup beef broth
¾ teaspoon celery salt
¼ teaspoon pepper
¼ teaspoon cinnamon
1 tablespoon cornstarch
2 tablespoons cold water

Directions
Step 1
In a skillet, brown roast on all sides in hot oil; drain. Place onion and sweet potatoes in slow cooker; top with roast. Combine broth and seasonings; pour over all. Cover and cook on low setting 7 to 8 hours or on high setting 4 to 5 hours.

Step 2
Place roast on a serving platter, surrounded with vegetables; keep warm. Combine cornstarch and water in a small saucepan; add one cup of juices from slow cooker. Cook and stir over medium heat until thickened and bubbly continue cooking and stirring 2 more minutes. Serve gravy with roast.