Shepherd'S Pie - cooking recipe

Ingredients

7 medium potatoes (about 2 lb.)
1 1/2 lb. medium sized mushrooms
1 (16 oz.) bag carrots
1 large stalk celery
1 medium onion
3/4 lb. ground beef
1/2 tsp. dried thyme leaves
2 tsp. salad oil
2 tsp. flour
2 Tbsp. Worcestershire sauce
2/3 c. skim milk
1 Tbsp. butter
1/8 tsp. pepper

Preparation

In 3-quart saucepan, over high heat, heat potatoes, with enough water to cover, to boiling.
Reduce heat to low, cover and simmer 25 to 30 minutes, until potatoes are fork-tender; drain.