This oven baked 3-ingredient corned beef and potato hash bake is straight out of my childhood. My grandpa used to throw it together on busy weeknights or lazy Sunday mornings, and it always disappeared fast. It’s almost unbelievable how much flavor you get from just corned beef, potatoes, and onions, but when they roast together in the oven, the edges get crispy, the centers turn tender, and everything tastes rich and savory. It’s the kind of no-fuss, family-style recipe that works for breakfast, brunch, or an easy dinner when you’re juggling a lot but still want something homemade.
Serve this hash bake hot, straight from the glass baking dish, with a simple green salad or steamed green beans to balance the richness. It’s also great with fried or soft-scrambled eggs on top if you’re making it for breakfast or brunch. A little ketchup, hot sauce, or grainy mustard on the side is perfect for dipping, and buttered toast or warm dinner rolls help scoop up all the crispy bits from the pan.
Oven Baked 3-Ingredient Corned Beef and Potato Hash Bake
Servings: 4

Ingredients
2 pounds russet or Yukon gold potatoes, scrubbed and cut into 1/2-inch cubes
2 cups cooked corned beef, cut into small chunks or shredded
1 large yellow onion, diced
Directions
Preheat your oven to 400°F (200°C). Lightly grease a 9x13-inch glass baking dish with a thin swipe of oil or cooking spray so the potatoes and corned beef don’t stick.
Add the cubed potatoes to the baking dish, spreading them out in an even layer so they roast instead of steam. Scatter the diced onion evenly over the potatoes.
Add the corned beef chunks on top, then use clean hands or a spatula to toss everything together right in the baking dish until the potatoes, onions, and corned beef are well mixed and evenly distributed.
Spread the mixture back into an even layer, making sure some of the corned beef and potatoes are touching the bottom and sides of the glass dish—those spots get the crispiest and most flavorful.
Cover the baking dish tightly with foil and bake for 25 minutes to help the potatoes start to soften and the flavors meld together.
Remove the foil, give everything a gentle stir to flip some of the potatoes and corned beef, then spread back into an even layer. Return the dish to the oven uncovered.
Bake uncovered for another 25 to 35 minutes, stirring once more halfway through, until the potatoes are tender in the center and the edges of the potatoes and corned beef are browned and crispy. Total time will depend on how small you cut the potatoes and your oven.
Once everything is browned to your liking, remove the dish from the oven and let it sit for 5 minutes to firm up slightly. Taste and, if you like, add a pinch of salt and pepper at the table. Serve hot, scooping from the glass dish so everyone gets some of the crispy bits from the bottom.
Variations & Tips
If you like things extra crispy, bump the oven up to 425°F (220°C) for the last 10 minutes and don’t stir—just let the top and edges really brown. You can swap in red potatoes for a slightly creamier texture that holds its shape well, or use a mix of russet and Yukon gold for contrast. If your corned beef is very salty, rinse it briefly and pat dry before cutting so the hash doesn’t get too salty as it concentrates in the oven. For make-ahead prep, you can cube the potatoes and onion and store them in cold water in the fridge for up to 8 hours, then drain and pat dry before baking; chop the corned beef the night before so all you have to do is toss and bake after work. If you want to stretch the recipe to feed more people without adding more ingredients, serve it with eggs on top or fold in a handful of leftover cooked potatoes you might have from another meal. For a slightly different flavor twist while still keeping the spirit of the dish, you can use red onion instead of yellow for a bit more sweetness, or toss the potatoes, onions, and corned beef with a tablespoon of the corned beef cooking liquid if you have it for extra savory depth.