Slow-Roasted Beef with Creamy Mashed Potatoes

Beef Stock:
3½lbs. meaty beef bones
3 cups coarsely chopped celery
3/4lb. carrots, chopped
2 tbsp. tomato paste
3 medium onions, peeled and halved
5 quarts water

Slow-Roasted Beef & Mashed Potatoes:
2 cups water
1 lb. boneless chuck roast, trimmed and cut against the grain into 4 slices
2 tsp. chopped fresh thyme
1/4 tsp. salt
1/8 tsp. white pepper
1½lbs. baking potatoes, peeled and cut into pieces
1/2 cup milk
1 tbsp. butter, softened
1/2 tsp. salt
1/4 tsp. white pepper

To make Beef Stock: Arrange bones in an even layer in a shallow roasting pan.
Bake at 400° for 45 minutes or until browned.

Transfer bones to an 8 qt. stockpot. Add celery, carrot, tomato paste, and
onions to pot; stir well to combine. Pour water over mixture; bring mixture
to a simmer. Reduce heat, and simmer 5 hours, skimming surface occasionally.

Strain stock through a sieve into a large bowl; discard solids. Cool stock to
room temperature. Cover and chill stock 8 to 24 hours. Skim solidified fat
from surface; discard. Refrigerate remaining stock in an airtight container
for up to 1 week or freeze for up to 3 months.

To prepare beef, combine 6 cups of Beef Stock and water in a saucepan; bring to
a simmer. Place beef in a 13 x 9 glass baking dish; pour stock mixture over
beef. Bake at 400° for 2 hours or until beef is tender.

Remove beef from the cooking liquid; cover and keep warm. Strain cooking liquid
through a sieve over a bowl. Place a zip-top bag inside a 2-cup
glass measure. Pour liquid into bag; let stand 10 minutes (fat will rise to
the top). Seal bag; carefully snip off 1 corner of bag. Drain liquid into a
saucepan, stopping before the fat layer reaches the opening; discard fat.
Bring liquid to a boil; reduce to simmer. Cook 20 minutes or until reduced
to 1 cup. Remove from heat; stir in 1 tsp. thyme, 1/4 tsp. salt, and 1/8 tsp. pepper.

To prepare potatoes, place potatoes in a saucepan; cover with water. Bring to a
boil. Reduce heat, and cook 12 minutes or until very tender. Drain.
Return potatoes to pan. Add milk, butter, 1/2 tsp. salt, and 1/4 tsp.
pepper; mash with a potato masher to desired consistency. Cook for 2 minutes
or until thoroughly heated. Serve with beef. Serve sauce over beef;
garnish with remaining thyme.