This corned beef casserole is a warm, comforting dish made with tender corned beef, fluffy potatoes, and creamy cheese. It’s perfect for a cozy dinner!
I love how easy it is to throw together—just mix and bake! It gives leftovers a tasty new life, and the cheesy topping is always a hit with my family. 🍽️
Key Ingredients & Substitutions
Mashed Potatoes: You can use any type of potatoes, but Yukon Golds are my favorite for their creamy texture. If you’re short on time, store-bought mashed potatoes work too. Just make sure they’re not too watery!
Corned Beef: Always cooked and chopped. If you don’t have corned beef, cooked brisket or even shredded chicken can make a good fill-in! For a vegetarian option, try using cooked lentils with similar spices.
Shredded Cheddar Cheese: Cheddar is great for flavor, but feel free to try other types like Monterey Jack or Gruyère for a different twist. A mix of cheeses can also add depth to the flavor.
Diced Onion: I prefer yellow onions because they’re sweet when cooked. For a milder taste, you could use green onions or shallots instead.
Sour Cream: Greek yogurt is an excellent substitute if you’re looking for a healthier option. It gives a similar tanginess and creaminess to the dish.
How Do I Cook the Onions Perfectly?
Cooking the onions until they’re soft and translucent adds flavor to the casserole. Here’s how to do it:
- Start with medium heat to prevent browning too quickly. Melt butter in a skillet.
- Add diced onions and let them cook down, stirring occasionally. This should take about 4-5 minutes.
- You’ll know they’re done when they look soft and glassy, which enhances their sweetness.
This step makes a significant difference in the overall taste of your casserole, so don’t rush it! Enjoy the process of building flavors.
How to Make Corned Beef Casserole
Ingredients You’ll Need:
Base Ingredients:
- 4 cups mashed potatoes (prepared with butter and milk)
- 2 cups cooked corned beef, chopped or shredded
- 1/2 cup diced onion
- 1 cup sour cream
- 1 tablespoon Dijon mustard (optional)
- 2 tablespoons butter
- Salt and pepper to taste
Cheesy Topping:
- 1 cup shredded cheddar cheese (divided)
For Garnishing:
- 1/4 cup chopped fresh parsley or chives
How Much Time Will You Need?
You’ll need about 15 minutes for preparation and 30-35 minutes for baking. So, in total, plan for about 50 minutes from start to finish. Perfect for a cozy family meal!
Step-by-Step Instructions:
1. Preheat the Oven:
Start by preheating your oven to 375°F (190°C). While it’s heating, take a baking dish and lightly grease it with some cooking spray or butter to prevent sticking.
2. Cook the Onions:
In a skillet, melt the butter over medium heat. Add the diced onion and cook, stirring occasionally, until the onions are softened and translucent. This should take about 4-5 minutes. You want them nice and tender for the best flavor!
3. Mix the Base Ingredients:
In a large bowl, combine your creamy mashed potatoes, the cooked onions, sour cream, the optional Dijon mustard, half of the shredded cheddar cheese, and a sprinkle of salt and pepper. Mix everything together until it’s smooth and creamy—this is going to be delicious!
4. Add the Corned Beef:
Now, gently fold in the chopped corned beef into your potato mixture. Make sure it’s evenly distributed so every bite has that savory flavor.
5. Prepare for Baking:
Transfer the entire mixture to your greased baking dish. Spread it out evenly so it cooks nicely. Take the remaining cheddar cheese and sprinkle it generously on top for that melty goodness.
6. Bake the Casserole:
Place your casserole in the preheated oven and bake for about 25-30 minutes, or until the top is golden brown and bubbly. Your kitchen is going to smell amazing!
7. Broil for a Crispy Finish (Optional):
If you like a crispier top, you can broil the casserole for an additional 2-3 minutes. Just watch it closely to ensure it doesn’t burn—no one likes a charred top!
8. Cool and Garnish:
Once it’s done baking, remove the casserole from the oven and let it cool for a few minutes. This step is important because it allows the layers to set a bit. Just before serving, garnish with fresh chopped parsley or chives for a pop of color and freshness.
Enjoy your hearty and comforting corned beef casserole—it’s sure to be a hit at the dinner table!
Can I Use Leftover Corned Beef for This Casserole?
Absolutely! Leftover corned beef from your St. Patrick’s Day or any other meal is perfect for this casserole. Just chop or shred it and mix it into the potato mixture as directed!
Can I Make This Recipe Without Sour Cream?
Yes, if you’re looking for a lighter option or simply don’t have sour cream, you can substitute it with Greek yogurt or even cottage cheese for a different texture and taste.
How Can I Store Leftover Casserole?
Store any leftovers in an airtight container in the fridge for up to 3 days. You can reheat it in the oven at 350°F (175°C) until warmed through, or in the microwave, stirring occasionally for even heating.
What Can I Serve with Corned Beef Casserole?
This casserole is hearty enough on its own, but if you want a side, a light green salad or steamed vegetables pairs nicely. The freshness balances the richness of the dish!
