1-First Step: Preparation and Preheating Start by preheating your oven to 450°F with a rack in the center position. This high temperature is crucial for achieving that desired crispy exterior. While the oven heats, peel 4 pounds of Yukon Gold potatoes and cut them into 1½-inch pieces. Consistent sizing is important because it ensures all the potatoes cook at the same rate. Try to cut them into roughly equal chunks so some do not become mushy while others remain undercooked.

2-Second Step: The Special Boiling Technique In a large pot, combine the kosher salt, baking soda, potatoes, and 2 quarts of water. The combination of salt and baking soda is the secret weapon in this recipe. Bring the water to a boil over high heat, then reduce to a simmer and cook until the potatoes are tender, about 10 minutes. You should be able to easily pierce them with a knife, but they should not fall apart. Drain the potatoes and let them cool and dry for about 1 minute or longer. This drying period helps remove excess surface moisture, which is essential for crisping.

3-Third Step: Heating the Fat While the oven preheats and the potatoes boil, combine the olive oil, butter (if using), and smashed garlic cloves on a rimmed sheet pan. Place the sheet pan in the oven to heat the oil and infuse it with garlic flavor. This step is crucial because adding potatoes to cold oil will result in a greasy, soft texture rather than a crispy one. The oil should be sizzling hot when the potatoes hit the pan.

4-Fourth Step: Coating and Initial Roasting Carefully remove the hot sheet pan from the oven using oven mitts. Discard the garlic cloves at this point to prevent them from burning and becoming bitter during roasting. Add the potatoes in a single layer to the hot oil and butter mixture, then turn them to coat evenly. The single layer is important for proper air circulation and even browning. Bake for 20 minutes without disturbing the potatoes. This allows the bottoms to develop a nice crust before you flip them.

5-Fifth Step: Final Roasting for Maximum Crispiness After 20 minutes, turn the potatoes using a spatula. Be gentle to avoid breaking them, but make sure to expose all sides to the hot pan surface. Return them to the oven for another 30 minutes until golden and crispy. The potatoes should have a deep golden color and a satisfying crunch when you bite into them. If you prefer them even crispier, you can leave them for an additional 5-10 minutes, but keep a close eye to prevent burning.

6-Final Step: Finishing and Serving Remove the perfectly roasted potatoes from the oven and immediately toss them with fresh parsley and flaky salt. The flaky salt provides both seasoning and a delightful crunch, while the parsley adds freshness and color. Serve hot alongside your favorite main dishes. These crispy roast potatoes pair wonderfully with roasted meats, grilled proteins, or can even stand alone as a satisfying snack with your favorite dipping sauce.