With crispy edges and creamy centers, Roasted Potatoes and Onions turn a few everyday ingredients into a side dish that everyone looks forward to. Just 15 minutes of prep, then the oven takes over, so you have plenty of time to prepare the rest of your meal or kick back and relax.
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I love both how quickly this simple recipe comes together and that it goes with almost any main course. It’s one of those rare dishes that makes as much sense on a holiday table as it does as a dinner side on a random Tuesday.
You’ll toss thinly sliced potatoes and onion wedges in olive oil, then spread them out on a baking sheet for even roasting. As they roast, the edges of the potatoes turn irresistibly crispy, while the onions caramelize. A sprinkle of fresh thyme or rosemary adds a fragrant touch, and they’re ready to serve.
Table of Contents
Recipe at a Glance
- Prep Time: 15 minutes
- Total Time: 1 hour 15 minutes
- Yield: 4 servings
- Skill Level: Easy
Ingredients for Roasted Potatoes and Onions
- Potatoes: I use either Yukon Gold or another waxy variety like red potatoes. You want firm, smooth-skinned potatoes without any signs of sprouting or green spots.
- Red Onion: Onions on the sweet side are best here so they caramelize. I often use red onion, but any sweet onion will work well. You want a firm onion that feels heavy for its size.
- Olive Oil: Just your favorite daily-use olive oil.
- Fresh Thyme or Minced Fresh Rosemary: You’re finishing the dish with one of these, so you want it to be fresh and fragrant. Dried thyme works in a pinch, but not dried rosemary which can be woody.
- Kosher Salt and Freshly Ground Black Pepper
- Flaky Sea Salt (Optional): This isn’t a must, but I love to finish these with a sprinkle of a light, flaky sea salt like Maldon.
How to Make Roasted Potatoes and Onions
Arrange potato slices in a slightly overlapping layer on a parchment lined baking sheet and evenly scatter red onion wedges on top, breaking them into smaller pieces for better caramelization. Drizzle all with olive oil and season with salt and pepper.
Bake in an oven preheated to 400˚F for 50-60 minutes, stirring every 10-15 minutes, until the potatoes are tender but crispy at the edges, and the onions have softened and caramelized. Once done, transfer to a serving platter, garnish with thyme leaves, and optionally, sprinkle with flaky salt and serve.
Pro Tips
- Slice Potatoes Evenly: Do your best to slice potatoes uniformly so they cook at the same rate. A mandoline slicer makes quick work of this.
- Don’t Overcrowd or Layer Unevenly: Spread the potatoes and onions in an even, slightly overlapping layer on the baking sheet.
- Testing for Doneness: The potatoes are done when they are tender inside and crispy on the edges. Similarly, the onions should be soft and caramelized. Keep an eye on both toward the end of cooking time to prevent burning.
Recipe Options
- Instead of waxy potatoes, you can make this with thinly sliced sweet potatoes or russet potatoes for a fluffier texture.
- If you like a bright finish, squeeze fresh lemon juice over the dish just before serving.
- If you want to add some heat, a pinch of red pepper flakes at the end does nicely.
How to Store and Reheat
Store leftovers refrigerated in an airtight container for up to 3 days or freeze in a single layer and then transfer to a freezer-safe bag or container for longer storage (up to 3 months). To reheat, whether from the refrigerator or frozen, place them on a parchment-lined baking sheet in a 350°F (175°C) oven. Warm refrigerated leftovers for about 10 minutes and frozen ones for about 15 minutes, adjusting as needed, until they are heated through and crisp at the edges.
More Two-In-One Side Dish Recipes
- Roasted Broccoli and Carrots
- Roasted Potatoes and Broccoli
- Roasted Broccoli and Cauliflower
- Roasted Green Beans and Potatoes
Ingredients
- 1 1/2 pounds Yukon gold potatoes (or other waxy potato) thinly sliced
- 1 large red onion halved and cut into 1/4-inch-thick wedges
- 1/4 cup olive oil
- kosher salt and freshly ground black pepper to taste
- 1 tablespoon fresh thyme leaves or minced fresh rosemary
- flaky sea salt such as Maldon, optional
Instructions
- Preheat oven to 400 °F (204 °C).
- Line a baking sheet with parchment paper. Arrange potato slices in a thin, slightly overlapping layer and scatter red onion over the top in an even layer, breaking up some of the wedges into slivers that will caramelize. Drizzle olive oil, season with salt and pepper.
- Bake 50-60 minutes, stirring every 10-15 minutes, until potatoes are tender with some crispy edges and onions are soft with some pieces that are caramelized. Transfer to serving platter; sprinkle with thyme leaves and finish with flaky salt if desired. Serve hot.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Wow, those potatoes look fantastic! They’re so thin and golden. I could eat this entire pan! And these are the perfect side dish for almost any sort of dinner recipe.
haha…they are addictive! Thank you, David.
this whole baking dish of potatoes and onions could be my lunch today. Maybe with some sour cream.
I love how you think, Mimi!