Potatoes O’Brien
by Sommer Collier — on Sep 14, 2026 In my version of Potatoes O’Brien I keep things similar to the classic American recipe as far as ingredients go, and use only a combination of diced potatoes, sweet green and red bell peppers, onions, olive oil, and a few spices. But in this recipe, I oven roast the veggies for maximum efficiency and flavor! That way I get all of the crispy, golden-brown potatoes I love for breakfast or dinner, with minimal effort.
I’m definitely a meat and potatoes kind of gal… Heavy emphasis on the potatoes! Tender, starchy, carby, perfectly fluffy potatoes in practically any form are one of my top love languages. I think my potato pie recipe is a great example of a dish that takes some effort to make and is totally worth it. Then there are other recipes that aren’t as complicated but still taste just as amazing! Potatoes O’Brien is a classic easy and rustic recipe where the potatoes are simply peeled and diced, then mixed with red and green bell peppers, onions, and seasonings. Although they are sometimes cooked in the skillet, I prefer to roast them in the oven… That way, the exteriors get a little crisp while the inside stay nice and fluffy!
Table of Contents
Sommer’s Recipe Highlights
Simple Veggie Dish – There is no dairy or eggs, no meat, and no gluten in here. Just fresh veggies, oil and spices! Without any special tweaks or tricks, O’Brien potatoes is a fantastic vegan, vegetarian, and gluten-free dish for everyone.
Hands-Off Cooking – I love love side dish recipes that roast in the oven on a baking sheet. And even better when prep is quick and easy, too! From start to finish this recipe takes only 45 minutes, and a little over half of that is oven cooking time. Aside from a quick flip halfway through cooking, there is no babysitting the pan or complicated steps.
Plays Well with Others – Like my shredded hash browns recipe, O’Brien potatoes are a great dish for any time of day, and go well with nearly any proteins! The bright bell peppers and simple seasonings lean towards a Tex-Mex flavor, so they’re especially delicious in meals that have a southwest vibe.
Key Ingredients and Tips
- Potatoes – Traditional Potatoes O’Brien recipes are made with russet potatoes, which are hearty and hold up well to cubing and roasting. (Which is why they’re also my favorite for my crispy skillet potatoes, too!)
- Veggies – I use both red and green bell peppers, but you can use whatever color peppers you prefer. Yellow, orange, and red tend to be fairly sweet, while green ones are the most mellow. I also use yellow onion, which are sweeter and more mild versus white onions, too.
- Spices – I use a combination of garlic powder, salt and pepper to season the vegetables.
- Olive oil – This is my favorite high-heat oil for roasting. Feel free to use avocado oil or canola oil, if you want.
- Parsley or green onions- Whichever you prefer, a sprinkling of some fresh herbs at the end of cooking really balances that oven roasted heaviness.
How to Make
Find the full ingredient proportions, detailed instructions, storage tips, and a video tutorial in the printable form at the bottom of the post.
Prep Veggies – I start by preheating the oven to 450 degrees Fahrenheit, and get out a large rimmed baking sheet and large bowl filled about halfway with water. As the oven warms, I peel and dice the potatoes into small 1/2-inch cubes. Make them as uniform as possible so they cook evenly, and add them to the bowl of water as you work. This keeps them from oxidizing and turning brown.
Next, I dice the peppers and onions into pieces that are about the same size as the potatoes, and dump those onto the baking sheet. Then I drain the potatoes in a colander and pat them dry with a paper towel. The drier the better… Moisture is a big no-no when roasting potatoes in the oven! It will produce steam in the hot oven and make the potatoes soggy, and without that glorious caramelization. So when they are nice and dry, I dump the potato pieces onto the baking sheet with the other veggies.
Sprinkle and Drizzle – Now I sprinkle the salt, ground black pepper, and garlic powder evenly over the veggies, followed by the olive oil.
Toss and Spread – Then I use my clean hands to toss everything together, until the pieces of potatoes, peppers and onion are evenly coated in the oil and spices. Spread the veggies out across the baking sheet so they are in one layer, and not clumping up into mounds.
Bake, Flip, Bake – Into the oven they go! I set my timer for 15 minutes, and either work on another dish or actually sit down and chill for a sec. (Ha.) Whatever the case, after 15 minutes I carefully pull the taters out of the oven and use a spatula to flip and move everything around. Ideally, the vegetables will roast and be mixed around so that more than one side is crispy.
I slide the baking sheet back in the oven and set my timer again for either 10 or 15 minutes, depending on how golden the potatoes already are when I flipped them. I take the pan out when the pieces of potato, onion, and bell peppers are brown and lightly crispy. Then use a knife or fork to test them for doneness… You should be able to easily pierce the thickest potato piece. Once done, let them cool for a few minutes on the baking sheet before sprinkling with fresh chopped green onions or parsley and serving warm.
Serving Suggestions
Potatoes O’Brien is a fabulous savory side dish for breakfast and brunch. The umami-ness and slightly sweet taste from the peppers and onion are great to balance more heavy and rich proteins. Here are a few of my favorite pairings:
I also like to serve them as a Tex-Mex-style side dish for dinner. The perky veggies and seasonings go perfectly with proteins like:
Storage Notes
Like most roasted vegetables, I find O’Brien potatoes have the best texture and flavor soon after they’re made. This is when they are most crispy on the outside and tender inside. That being said, leftovers will keep well for up to 3-4 days in the refrigerator when stored in an airtight container.
I always reheat leftovers either in the oven or air fryer. Just not the microwave! Microwaving with release even more moisture and cause the potatoes, bell peppers, and onions to become unpleasantly soft. Instead, I bake them for 10-15 minutes in a 400 degree oven, flipping them around about halfway through the cooking time. To air fry, heat your air fryer to 375 degrees and cook the veggies for 5 minutes, shaking the basket around the 3 minute mark. And nope, you don’t need to add any more oil!
Frequently Asked Questions
Yes, you can! If you are using frozen diced potatoes, don’t thaw them first or they’ll release extra moisture and it will be nearly impossible to get them dry enough to roast. Instead, toss them onto the baking sheet while frozen, and proceed to season and bake them per usual. You will just likely need to cook them on the high end of 30-35 minutes to get the potato pieces fork-tender.
Soggy potatoes are usually caused by the veggies being too wet when seasoned and/or before roasting. This is likely either from not drying them properly after draining the potatoes, or adding a bit too much oil before roasting. OR it could be that the potatoes and vegetables were overlapping on the baking sheet. Remember to take care and spread everything out on the baking sheet, so the small pieces don’t lay on top of each other!
I use a nonstick baking pan with a nice deep lip, so I never really have a need to line it. Parchment paper usually has a heat limit of only around 430 degrees, and is therefore not suited for high-heat roasting. I also don’t suggest aluminum foil… Even coated in oil, the vegetables are likely to stick.
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More Side Dish Recipes
Potatoes O’Brien
Video
Ingredients
- 4 cups diced potatoes ½ inch cubes
- 1 cup diced green bell pepper
- 1 cup diced red bell pepper
- 1 cup diced onion
- 2 teaspoons salt
- 1 teaspoon ground black pepper
- 1 teaspoon garlic powder
- 2 tablespoons olive oil
- 2 tablespoons chopped parsley
Instructions
- Preheat the oven to 450°F. Peel the potatoes then dice them into small ½ inch cubes. As you finish dicing each potato, place them in a bowl of cold water to soak. This keeps them from oxidizing and turning brown as they sit.
- Dice the bell peppers and onions. Then drain the potatoes in a colander and pat them dry with paper towels.
- Set out a large rimmed baking sheet. Pour the diced potatoes, peppers, and onions on the baking sheet. Then sprinkle the top with salt, pepper, garlic powder. Drizzle olive oil over the top and toss well to season and coat all of the veggies.
- Spread the potatoes O’Brien out in a single layer on the baking sheet. Bake for 15 minutes. Flip and continue to bake for another 10-15 minutes until golden and crispy. Serve warm.
