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Savory corned beef casserole is a delicious way to use up leftovers. Layer buttery potatoes, briny meat, and earthy vegetables in a creamy milk sauce for a comforting bake that’s easy to make!
There’s nothing like a couple of delicious casseroles to use up leftover ingredients that you have in the kitchen after a big meal. And with St. Patrick’s Day coming up, I’m sure to have leftover corned beef taking up fridge space.
Corned beef casserole is the perfect fix. I take traditional Irish flavors and layer them together into something new, improved, and delicious! Beginning to end, this recipe takes just over an hour to prepare. The prep time, however, is minimal.
Keeping with tradition, I recommend trying my Guinness Irish Stew for a St. Patrick’s Day meal. It’s a thick, savory stew with rich meat and vegetables. Irish Mashed Potatoes, or colcannon, make a great side and are packed with flavor.
If you want to do it all homemade, from beginning to end, then check out a reader favorite, my guide on How to Make Corned Beef in your own kitchen.
INGREDIENT NOTES AND SUBSTITUTIONS
- Corned Beef – This salt-cured meat is very tender and tastes a bit briny and sour. It goes very well with a number of vegetables, and can be prepared a number of ways.
- Russet Potatoes – This large potato is easy to slice and fantastic for casseroles. White potatoes, which keep their shape almost as well, can be used as a substitute.
- Milk & Flour – These two will be mixed together and poured over the dish, helping to bind the ingredients and set the dish.
- Butter – Melted into the milk, it will be soaked up by the potatoes for a delicious, rich flavor.
- Shallots – Sweeter and milder than onions, these even has a subtle garlic flavor. A yellow onion can be substituted in a pinch.
- Brussels Sprouts – Earthy and a bit bitter, these veggies soften and become slightly sweet and savory. You can use sliced cabbage, if preferred.
- Parmesan – This hard cheese is easy to grate and sprinkle over casseroles, vegetables, and salads. It is mild, sweet, and a bit salty. Some recipes use swiss cheese instead. For a substitute with similar textures and flavors, you can use asiago or romano cheese.
HOW TO MAKE CORNED BEEF CASSEROLE
1. Preheat. Preheat the oven to 425°F.
2. Slice the Ingredients. Cut the potatoes into ¼” slices, using either a mandolin or a sharp knife so they are all an even thickness. Next, thinly slice the meat, shallots, and brussels sprouts. Set aside.
3. Cook the Potatoes. Add the sliced potatoes to a pan, then pour the milk and butter over the top. Allow the milk to come to a boil before covering the pan and lowering the heat. Simmer the potatoes, keeping the heat low. After 8 minutes, allow the mixture to become cool enough to handle before removing the potatoes. Layer. Lay the potato slices on the bottom of an oiled or buttered casserole dish. Set aside the milk and butter mixture. Layer the meat, shallots, and brussels sprouts one at a time. Add more layers until all of the ingredients are used.
4. Top and Bake. Add flour to the boiled milk and butter mixture and whisk well. Pour over the entire dish. Finally, top with the Parmesan cheese and place the dish in the oven. Bake for 50 minutes until the top becomes a deep, crispy brown.
5. Serve! Give the dish at least 15 minutes to cool, which will help it set for easier slicing.
What vegetables can I use in a corned beef casserole?
My recipe uses cabbage and sometimes I’ve used mushrooms. Green peppers are also sometimes used for a different texture and aroma.
Really, most vegetables would taste delicious in this casserole!
Can I freeze corned beef casserole?
This casserole isn’t the best to freeze after cooking, as the layers and ingredients may become mushy. Also, dairy tends to curdle when thawed and reheated.
You can, however, freeze the sliced meat and thaw it in the refrigerator when you’re ready to prepare the recipe!
What is the best way to heat leftover casserole with corned beef?
Pop your leftover pan right back in the oven to reheat! This will keep it crispy. Because this is the best way to reheat, refrigerate your leftover dish in the same pan it was baked in.
Corned Beef Casserole
- Preheat oven to 425°F. Coat a 9×9” casserole dish with oil or butter, set aside.
- Using a mandolin or knife, slice the potato into 1/4 inch slices. Slice the cooked corned beef thin and set aside. Slice the shallots and Brussels sprouts thin and set aside.
- In a large saucepan add the sliced potato and cover with milk and butter. Bring to a boil, lower heat and simmer 8 minutes. Turn off heat and allow to cool, enough to handle. Reserve the milk and butter, set aside.
- Layer the potato then the corned beef slices, shallots and Brussels sprouts. Repeat again using all ingredients.
- Whisk the flour into the milk and pour milk over all and top with Parmesan cheese. Bake for 50 minutes. Top will be a deep, crispy brown. Allow to cool at least 15 minutes before slicing to serve.
The information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for a professional nutritionist’s advice.