Oven-roasted potatoes and onions are a simple, savory side with crisp, golden edges and tender centers. Cutting the vegetables to a similar size, giving them room on the pan, and roasting at high heat lets the potatoes brown while the onions turn sweet and soft.
Ingredients
- 2 pounds Yukon Gold or red potatoes, scrubbed and cut into 1-inch chunks
- 1 large yellow onion, peeled and cut into 1-inch wedges
- 3 tablespoons olive oil
- 1 teaspoon kosher salt
- ½ teaspoon freshly ground black pepper
- 1 teaspoon garlic powder
- 1 teaspoon dried rosemary or dried thyme
- 1 tablespoon chopped fresh parsley, for serving (optional)
Instructions
- Heat the oven. Arrange a rack in the center of the oven and heat it to 425°F (220°C). Line a large, rimmed baking sheet with parchment for easier cleanup, if you like. The vegetables brown best when they can sit directly on a hot pan, so skip the parchment if maximum crispness is your priority.
- Prepare the vegetables. Cut the potatoes into roughly 1-inch pieces so they cook at a similar rate. Cut the onion into wedges about the same width, leaving a little of the root end attached to help the layers hold together. If using especially small potatoes, halve or quarter them rather than cutting them into tiny pieces.
- Season. Put the potatoes and onion in a large bowl. Add the olive oil, salt, pepper, garlic powder, and rosemary or thyme. Toss thoroughly until the surfaces are lightly coated. If a few dry-looking spots remain, add a little oil, no more than about a teaspoon at a time.
- Arrange on the pan. Spread the vegetables in one layer on the baking sheet, with some space between pieces and the cut sides of the potatoes facing down where possible. Use two pans if necessary; crowding traps steam and makes the potatoes soft rather than browned.
- Roast until tender and golden. Bake for 20 minutes, then turn the potatoes and gently stir the onions. Continue roasting for 15 to 25 minutes, checking near the end, until the potatoes are browned outside and easily pierced in the center with a fork. The total time is usually 35 to 45 minutes, depending on the potato size, pan, and oven.
- Finish and serve. Taste and add a pinch more salt or pepper if needed. Scatter with parsley, if using, and serve hot. For the best texture, transfer the vegetables off the hot pan once they are done so they do not continue cooking in residual heat.
Tips
- Choose a suitable potato. Yukon Gold and red potatoes hold their shape and have a creamy interior. Russets work too, but they are starchier and can break apart more readily; cut them into generous chunks and turn them gently.
- Keep the pieces even. Uneven cuts lead to some pieces burning before others are tender. If your onion wedges are much thinner than the potatoes, add them after the potatoes have roasted for about 10 minutes so the onion does not get too dark.
- Use enough space. A crowded pan is one of the main causes of pale, soggy roasted vegetables. Divide the batch between two rimmed pans rather than piling the vegetables up. If using two oven racks, switch the pans’ positions halfway through.
- Adjust the seasoning thoughtfully. Fresh herbs can burn at this temperature, so add delicate herbs such as parsley after roasting. If using salted butter or a salty seasoning blend, reduce the kosher salt and taste before adding more.
Serving Suggestions
Serve these potatoes and onions alongside roast chicken, grilled sausages, steak, pork chops, baked fish, or a simple bean or lentil dish. They also make a satisfying breakfast side with eggs. For a fresh contrast, pair them with a green salad dressed with lemon or vinegar, or add a spoonful of plain yogurt or sour cream at the table. If serving a crowd, keep the finished vegetables on a warm platter and bring them out promptly; they are most crisp soon after roasting.
Variations
For a smoky version, replace the rosemary with ½ teaspoon smoked paprika. Add ½ teaspoon ground cumin for a warmer, earthier flavor. To include carrots or bell peppers, cut them into pieces about the same size as the potatoes; softer vegetables may need to be added partway through roasting to avoid overcooking. You can also toss the hot vegetables with 1 to 2 tablespoons grated Parmesan or a squeeze of lemon juice just before serving. For a more garlicky finish, add one small minced garlic clove during the final 5 minutes rather than at the start, when it can burn.
Storage and Reheating
Cool leftovers promptly and place them in a covered, shallow container in the refrigerator within 2 hours of cooking. Keep them refrigerated for up to 3 to 4 days. Reheat in a 400°F (205°C) oven or toaster oven for about 10 to 15 minutes, spreading the vegetables on a baking sheet and turning once, until steaming hot throughout. An air fryer also works well at 375°F (190°C) for about 5 to 8 minutes; check and shake the basket as needed. Microwave reheating is convenient but softens the browned surfaces. Reheat only the portion you plan to eat, and do not leave cooked potatoes at room temperature for more than 2 hours (1 hour if the room is above 90°F/32°C).
Frequently Asked Questions
Do I need to boil the potatoes before roasting?
No. One-inch chunks roast through in about 35 to 45 minutes at 425°F, so parboiling is unnecessary for this recipe. If your pieces are larger, expect a longer roasting time and test the centers with a fork.
Should I peel the potatoes?
Peeling is optional. Scrub the potatoes well and leave the skins on for extra texture and less prep, or peel them if you prefer a smoother bite. Remove any eyes, green areas, or damaged spots before cutting.
Why are my potatoes not crispy?
They may be crowded, insufficiently coated with oil, or roasted on a pan that was too cool. Spread the pieces in a single layer, preheat the oven fully, and avoid opening the door repeatedly. A metal sheet pan usually browns more effectively than a deep glass baking dish.
Can I make the vegetables ahead?
You can cut the potatoes a few hours ahead and keep them submerged in cold water in the refrigerator to prevent browning. Drain and dry them very thoroughly before adding oil and seasoning. Cut onions closer to roasting time for the freshest flavor, and roast the vegetables just before serving for the best texture.
Can I use fresh garlic?
Yes. Minced fresh garlic can scorch during a long roast, so stir it into the vegetables during the last 5 to 10 minutes, or toss it in after roasting with a little oil. Garlic powder is convenient because it withstands the full cooking time.
How can I tell when they are done?
The potatoes should have golden, browned edges and feel tender when pierced in the thickest part with a fork or small knife. If they brown before becoming tender, lower the oven to 400°F and continue cooking, checking every 5 minutes.