Golden Crispy Roasted Potatoes and Onions Step-by-step instructions

Before you start

Before starting, heat the oven to 425°F (220°C). Scrub the potatoes well—leaving the skin on adds texture and nutrients. Slice them into even 1/2-inch rounds so they cook at the same rate. Peel the onion and cut it into wedges.

Mince the garlic and chop the fresh herbs. Measure the olive oil, butter, salt, and pepper. Have a large rimmed baking sheet ready. Toss everything together in a bowl right before spreading on the pan, so the herbs stay vibrant.

Instructions

Prep and Toss

1. 1Prepare the Potatoes and Onions
   Heat the oven to 425°F (220°C). Scrub the potatoes and slice them into 1/2-inch rounds. Peel the onion and cut it into wedges about 1 inch wide. Place the potato slices and onion wedges in a large mixing bowl.
   Look for The potato slices should be uniform in thickness so they roast evenly.
   Tip Leaving the skin on the potatoes adds texture and helps them hold their shape.
2. 2Season the Vegetables
   Add the olive oil, melted butter, minced garlic, thyme, rosemary, salt, and pepper to the bowl. Toss everything with a spatula until the potatoes and onions are evenly coated with the herb mixture.
   Look for Every potato round should glisten with the oil and herbs.
   Tip Toss gently to avoid breaking the potato slices.

At the end of this phase, the potatoes and onions should be evenly coated with the herb mixture, and the oven should be fully preheated. The potato slices should be uniform in thickness, and the onions should be in bite-sized wedges. The seasoning should look evenly distributed—you can see flecks of thyme and rosemary. The garlic should be minced fine so it doesn't burn. This is a quick phase, but it sets the stage for a perfect roast.

Roast to Golden

3. 3Arrange on the Baking Sheet
   Spread the potatoes and onions in a single layer on a large rimmed baking sheet. Make sure the potato slices are not overlapping too much; this allows the edges to crisp up.
   Look for The vegetables should be in one even layer, with space between pieces.
   Tip If the pan is crowded, use two sheets or roast in batches.
4. 4Roast Until Golden and Crispy
   Place the baking sheet in the oven and roast for 35 to 40 minutes, flipping the vegetables halfway through with a spatula. Roast until the potatoes are deep golden brown and crispy on the edges, and the onions are caramelized and tender.
   Look for The edges of the potatoes should look browned and crisp, and the onions should be soft and golden.
   Tip The exact time may vary depending on the thickness of the potato slices.

After 35 to 40 minutes, the kitchen will smell of roasted garlic and herbs. The potatoes should be deep golden brown with crispy edges, and the onions will be soft and caramelized, with some charred spots. When you flip them, you should see browned bits on the bottom.

The potatoes should be tender when pierced with a fork. If they're not yet crispy, give them a few more minutes. The pan might have some browned bits—these are delicious and can be scraped up and served.

Serve

5. 5Serve Hot
   Transfer the roasted potatoes and onions to a serving plate. Serve immediately while they are hot and crispy.
   Look for The potatoes should be crunchy on the outside and fluffy inside.
   Tip For extra crispiness, let them rest on the baking sheet for a minute before serving.

The final dish should look inviting: golden potatoes with crispy edges, soft caramelized onions, and a glossy sheen from the herb butter. The aroma is rich and savory. When you cut into a potato, the inside should be fluffy and tender, not dry. The onions should be sweet and almost jammy. Serve immediately while they are still hot and crisp. If you wait too long, the crispiness will soften, but they will still taste great.

Common mistakes

The most common mistake is overcrowding the pan. If the potatoes overlap, they steam instead of roast, and you'll end up with soft, pale potatoes. Another issue is not flipping them halfway through—this leads to one side being crispy and the other soft.

Also, be careful not to use too much oil, which can make them greasy. Use just enough to coat. Finally, don't skip the preheating; a hot oven is crucial for crisping. If the potatoes are browning too fast but aren't tender, lower the heat to 400°F (200°C) and continue roasting.

How to tell it’s done

The potatoes are done when they are deep golden brown and crispy on the edges, and a fork easily pierces the center. The onions should be soft and caramelized, with some browned spots.

If you want extra crispiness, you can leave them in the oven for another 5 minutes, but watch closely to prevent burning. The internal temperature of the potatoes doesn't apply here, but the texture will tell you. Let them rest for a minute before serving—this helps the crust set.