Preheat your oven to 425°F (220°C). A hot oven is essential for achieving that crispy exterior on the potatoes.
In a large mixing bowl, combine the cubed potatoes with olive oil, sea salt, black pepper, lemon zest, lemon juice, minced garlic, and rosemary. Toss everything together until the potatoes are well-coated in the mixture.
Spread the seasoned potatoes in a single layer on a baking sheet. Make sure they are not overcrowded; this allows them to roast evenly and get crispy.
Place the baking sheet in the preheated oven and roast for about 25-30 minutes. Halfway through, use a spatula to flip the potatoes to ensure even browning.
The potatoes are done when they are golden brown and crispy on the outside and fork-tender on the inside. If needed, you can roast them for an additional 5-10 minutes.
Once roasted to perfection, remove the potatoes from the oven and let them cool for a few minutes. Serve warm as a delightful side dish to your favorite main courses.
