Baked Potato Casserole
["9 large potatoes (about 5 lb.)", "2 (3 oz.) pkg. cream cheese", "1 c. sour cream", "2 tsp. onion powder or salt", "1 tsp. salt", "1/4 tsp. pepper", "2 Tbsp. butter or margarine"]
["Cook peeled potatoes in boiling salted water until tender. Drain and mash potatoes until smooth (no lumps).", "Add remaining ingredients; beat until light and fluffy.", "Cool.", "Cover and place in refrigerator.", "May be used any time within 2 weeks."]
["potatoes", "cream cheese", "sour cream", "onion powder", "salt", "pepper", "butter"]