Weeknight Shepherd’s Pie: A Cozy Leftover Roast Beef Meal
Sneak Preview: Got leftover roast beef? Turn it into a cozy Weeknight Shepherd’s Pie! This easy, satisfying casserole gives your Sunday pot roast a delicious second act.
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If your family can predict the menu for days after a beef roast, surprise them. This hearty dish transforms leftovers into something entirely new—maybe even better than the original pot roast and potatoes!
Leftovers have never been this comforting.
Why This Recipe Belongs in Your Rotation
- A tasty alternative to reheating leftovers
- Quick to assemble with pre-cooked meat
- Easily customizable with veggies or mashed cauliflower
Happy Cooks Speak Up
“Absolutely yummy recipe! Used left over Tri-tip and it was perfect. Thank you for giving me another great go-to recipe! Family loved it too!!” — CHRISTY M.
Shepherd’s Pie or Cottage Pie?
Technically, Shepherd’s Pie uses lamb, while Cottage Pie uses beef. Oops—I called it Shepherd’s Pie, but this version uses roast beef.
Still, most Americans use “Shepherd’s Pie” for both, and Google agrees—so here we are!
Got Leftover Roast Beef?
I call this a “Weeknight” recipe because we often have pot roast or this deviled Swiss chuck steak on Sunday, which makes this an easy leftover beef recipe for the following week.
When faced with leftover roast beef, I often debate between this Weeknight Shepherd’s Pie, Vegetable Beef Soup, Steak and Mushroom Soup, Leftover Brisket Quesadillas, or these Memorable Green Chile Beef Enchiladas—all delicious ways to repurpose leftovers.
Ingredients and Substitutions
1. Leftover Roast Beef (or Ground Beef)
Many people swap in 1 pound of ground beef instead of leftover roast beef. If you don’t have leftovers, you can:
✔ Use thin slices of leftover steak
✔ Shred beef stew meat
✔ Grab sliced roast beef from the deli
2. Mashed Potatoes (or Mashed Cauliflower)
Got leftover mashed potatoes? Perfect. If not, the recipe below includes quick instructions.
✔ Low-carb? Mashed cauliflower works beautifully! If you use my mashed cauliflower recipe, your family might not even notice the difference.
4. Vegetables
✔ Mushrooms: Love ‘em or leave ‘em
✔ Corn or green beans: Great substitutes for peas and carrots
✔ Onions & garlic: Essential for flavor
How to Make the Mashed Potato Topping
1️⃣ Cook Potatoes: Boil three peeled potatoes until tender. Drain well.
2️⃣ Instant Pot (paid link): Add 1½ cups water and peeled, chopped potatoes. (Bonus: Throw in a couple of garlic cloves!)
3️⃣ Pressure cook on high for 10 minutes, quick release, and drain.
4️⃣ Mash with a potato masher until smooth.
5️⃣ Season with salt and pepper to taste.
How to Assemble the Meat Layer
1️⃣ Sauté onions in oil until softened.
2️⃣ Add mushrooms (if using) and cook until tender.
3️⃣ Stir in frozen peas and carrots (or leftover carrots from your roast).
4️⃣ Cut leftover roast beef into bite-sized pieces and mix with veggies.
5️⃣ Add leftover gravy (or prepared brown gravy). Too dry? Add beef broth, water, or condensed cream of mushroom soup.
6️⃣ Sprinkle with thyme, Worcestershire sauce, or soy sauce for extra flavor.
👩🍳 Pro Tip: If your roast beef is too chewy, it probably wasn’t cooked long enough. Simmer it in broth until fork-tender—this can take 1 to 3 hours.
How to Assemble & Bake
1️⃣ Use a spring-loaded ice cream scoop for easy spreading.
2️⃣ Use a spatula to spread mashed potatoes over the beef mixture.
3️⃣ Drizzle with melted butter and sprinkle with paprika or smoked paprika .
4️⃣ Bake at 350°F (170°C) until golden brown and bubbly.
5️⃣ Garnish with fresh thyme or parsley
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Parting Thoughts: What did your mom do with roast beef leftovers? A friend says his mom made roast beef hash every Monday, starting with Sunday’s pot roast and potatoes. Too bad she didn’t have this recipe to mix up the routine!
Need help troubleshooting? Email me: Paula at saladinajar.com—photos welcome!
Weeknight Shepherd’s Pie: A Cozy Leftover Roast Beef Meal
Video
Ingredients
Mashed Potato Topping:
- 3 medium (639 g) potatoes, peeled
- ½ cup (114 g) milk
- 2 tablespoons butter
- ½ teaspoon salt
- ¼ teaspoon white pepper
Meat Layer:
- 1 tablespoon vegetable oil
- ¼ cup (13 g) fresh or frozen onion, chopped fresh, or frozen
- 4 ounces (113 g) fresh mushrooms, sliced or chopped or 2 oz. canned mushrooms, sliced
- 1 cup (140 g) frozen peas and carrots
- 1 .87 oz package (24 g) brown gravy mix + 1 cup water or use leftover gravy
- 1 package (482 g) beef roast au jus-17 ounces or 2-3 cups leftover beef roast, fork-shredded or cut into chunks
- ¼ teaspoon dried thyme
- freshly-ground pepper
- paprika
- 2 tablespoon (28 g) butter thin slices
Instructions
Step 1: Preheat Oven
- Preheat your oven to 350˚ F (180˚C).
Make the Mashed Potato Topping
- Peel and chop 3 medium potatoes.Cover with water, and boil until tender. Drain well.
- Mash potatoes until smooth. In a microwave-safe bowl, heat 1/2 cup (114 g) milk and 2 tablespoons butter in a microwave oven for 1 minute. Add to the potatoes. Season to taste with 1/2 teaspoon salt and 1/4 teaspoon white pepper
Prepare the Beef Layer
- Preheat a large skillet. Add 1 tablespoon vegetable oil. Sauté 1/4 cup (13 g) fresh or frozen onion, chopped in skillet until soft. Add 4 ounces (113 g) fresh mushrooms, sliced or chopped to onions, and continue to sauté until browned. Add 1 cup (140 g) frozen peas and carrots.
- In a small bowl, whisk together 1 .87 oz package (24 g) brown gravy mix + 1 cup water. Add the gravy mixture to the skillet along with 1 package (482 g) beef roast au jus-17 ounces and 1/4 teaspoon dried thyme. Stir and simmer until the mixture begins to thicken. Season with freshly-ground pepper
- 💡 If you have leftover gravy, you can skip the brown gravy mix!
Assemble the Casserole
- Lightly grease a 1-1/2 quart casserole dish. Pour the beef mixture into the dish and spread evenly.Carefully spoon mashed potatoes on top and swirl with a spatula. Sprinkle with paprika (optional) if desired and dot with 2 tablespoon (28 g) butter, thinly sliced.
Bake
- Bake in 350˚F (180˚C) oven for 20-25 minutes or until potatoes are golden on top and the beef mixture is bubbly.
Notes
Nutrition
All images and text ©️ Paula Rhodes for Salad in a Jar.com
Paula Rhodes, owner
As a retired home economist, I created Saladinajar.com to share my belief that you don’t have to be a chef to find joy in creating homemade food worth sharing. Bread machines (used in an unconventional way), homemade yogurt, and quick microwave recipes are my specialty.