So to me, homemade shepherds pie is technically a casserole rather than a pie but that’s beside the point. Now, this is technically a cottage pie rather than a shepherd's pie since we're using beef here. Should you want it traditional you'll just use ground lamb in place of the beef.
2.5 lbs (1200g) russet potatoes
1/2 cup (115g) butter
1/2 cup(120ml) milk
1/3 cup (85g) creme fraiche
1/2 cup (75g) parmigiano
Salt and pepper to taste
3 diced trumpet mushrooms (or 6 button mushrooms)
1 medium yellow onion
1 large carrot diced
1 rib celery diced
4 cloves garlic thinly sliced
1.5 lbs ground beef or lamb (lamb is traditional)
6 oz finely chopped or ground bacon
2 Tbsp (30g) tomato paste
2 Tbsp Worcestershire sauce
1 Tbsp(6g) fresh rosemary
1 Tbsp (5g) fresh thyme, minced
1/2 cup red wine
1 cup beef stock
1 cup 140g frozen peas
1/2 cup (75g) parmigiano, grated
1/2 cup (75g) gruyere, grated
Mashed Potato Method:
For the mashed potato toppings, rinse and peel the russet potatoes and cut lengthwise then lengthwise again and then into quarters.
Dump all potatoes into a medium pot and cover with water. Season generously with salt to taste. Set over medium-high heat.
Bring to a boil and let boil for 7-10 minutes. Potatoes should be easily pierced with a fork. Drain once finished.
In a small sauce pot, add in unsalted butter and whole milk. Set on the stove over medium heat just until the butter is melted and mixture is hot.
Rice/mash all the potatoes using a potato ricer or potato masher. Add in the hot butter/milk mixture and mix together before adding and stirring in creme fraiche.
Grate in gruyere cheese. Season to taste with salt and pepper and mix together until thoroughly combined.
If not using store bought ground beef, start by slicing the beef (or lamb) and thoroughly mix with roughly chopped bacon.
In a stand mixer fitted with a meat grinder attachment, grind the beef and bacon mixture. Once finished, knead into a firm dough like ball.
Heat a medium size pot (or pan) over medium-high heat until smoking hot. No oil included.
Add in the beef, pressing it in and sear for 3 minutes. Flip and repeat on the other side.
When both sides are seared. Mash the beef until fine, season with salt and pepper, and continue cooking over medium heat in its own fat until evenly brown.
Dump out all the beef into a separate bowl and place to the side.
Add butter to the pot (or pan) and melt over medium heat.
Once bubbling, add in diced mushrooms and sear until just brown before adding in the diced onions, diced celery, diced carrots, and sliced garlic cloves. Season with salt and pepper. Saute for 2-3 minutes mixing occasionally.
When softened, toss in tomato paste sauteing for 2 minutes or until caramelized. Deglaze with red wine, stock, or vinegar.
Follow with worcestershire sauce and bring to a boil. Add in fresh chopped thyme, fresh chopped rosemary, mix to combine and let reduce until all the liquid is gone.
Add in beef stock seasoning to taste with salt and pepper. Mix and let cook for 1-2 minutes.
Add in the frozen peas and stir together. Let cook until the peas are nice and hot.
Dump the meat and vegetable mixture into a casserole dish spreading out evenly to the edges of the pan. Press the meat down so it’s nice and compact.
Gently add the mashed potatoes on top and evenly spread across the surface of the casserole.
Grate on some Parmigiano Reggiano and gruyere cheese. Optionally fork the top of the surface.
Place into a 375F preheated oven for 20 minutes. Let sit for 20 minutes before serving.