Shepherd's Pie - Another Make-Ahead Meal

It's Monday again and we need another make ahead meal.  Last night we had some nice steaks and with the leftovers I decided to make a version of Shepherd's Pie.  To be honest, I'm not sure if this is remotely close to what Shepherd's Pie should taste like, but I am calling it that because I'm using chopped beef as the filling with mashed potatoes on top.  I hope it's good.

I took last night's beef, cut it into cubes, then chopped it up in a food processor.  
I browned the beef in olive oil, then added chopped onions and carrots.  
Then I added freshly chopped rosemary, thyme and sage.
Deglaze the pan with a tawny port and then add some beef stock and a little bit of milk.
Add a splash of Worcestershire.
Cover and simmer for about 10 minutes.
Adjust seasoning, adding kosher salt and pepper as needed.
Allow to cool a bit. 
Add some peas to the mixture.
Fill small individual portion shallow dishes about half way up.
Cover with mashed potatoes.
Cover with plastic wrap and refrigerate until ready to bake.

For the mashed potatoes, I used Yukon gold potatoes, cut them into 2-3" pieces and boiled them.  Once the potatoes are fall apart tender, drain, add cream and butter, more butter than cream and yes, until it seems unreasonable to be using so much butter, and mix together using a hand mixer.   Use a sliding scale for amount of butter to use.  How tasty do you want your potatoes?  The more tasty, the more butter you must use.  It's not what any of us want to hear, but it's the truth.  You could also use a potato ricer first to "mash" the potatoes, but I prefer to just throw the potatoes in with the butter and cream and whip them together.  Add salt as needed.

When ready to bake, heat oven to 400f.  Unwrap the pies and bake until pies are heated through and tops are slightly browned, about 20 minutes.

I must admit, this was better than anticipated.  I was not thrilled about dinner, but I ate every last scaping bite.  I will do chicken pot pies the same way...buttery mashed potatoes on top!