This is the mashed potato casserole. If you con't have access to it, PM me and I'll cut and paste for you. BTW, unless you want to feed an army (as my mother would say), cut the recipe in half.

https://cooking.nytimes.com/recipes/...ion=all&rank=2

For the gravy, not sure where it's from - but I used turkey stock instead of the bouillon and water but it works great for any kind of gravy. You can make it a day or two ahead and then, on the big day, heat and just add the pan drippings for more flavor and thicken with flour, if necessary.

INGREDIENTS
¼ cup unsalted butter
¼ cup flour
1 teaspoon onion powder
2 cups water
4 teaspoons beef (or chicken) bouillon granules

INSTRUCTIONS
Combine water and bouillon in a heat proof container (I use my glass measuring cup). Heat the broth in microwave 1 minute at a time, until it is steaming hot.
Melt butter in a medium saucepan over medium heat, add flour and onion powder and whisk together. Allow to cook for 1 minute, whisking occasionally (this helps cook out the ‘floury’ taste).
Add broth to flour mixture and whisk.
Bring to boil, reduce to simmer for 1 minute.