Follow these steps carefully to achieve perfectly roasted, beautifully glazed carrots and potatoes every time. The process involves two main roasting phases to ensure both proper cooking and optimal glaze application.

1. Preheat Oven and Prepare Baking Sheet: Begin by preheating your oven to 400°F (200°C). Position an oven rack in the center of the oven for even heat exposure. Line a large, heavy-duty, rimmed baking sheet with parchment paper. This is highly recommended for two reasons: it prevents the vegetables, especially once coated in honey glaze, from sticking stubbornly to the pan, and it makes cleanup significantly easier. If you don’t have parchment paper, you can lightly grease the pan with a bit of oil, but be prepared for potentially more sticking. A rimmed sheet is important to prevent any oil or juices from dripping into your oven.
2. Prepare the Vegetables (The Foundation): Thoroughly wash the potatoes and carrots. Peel the carrots. Decide whether to peel the potatoes (recommended for thicker-skinned varieties like Russets) or leave the skins on after a good scrub (ideal for Yukon Gold or red potatoes). Pat the vegetables dry with paper towels; removing excess surface moisture helps them roast rather than steam, leading to better browning. Chop both the carrots and potatoes into roughly uniform 1-inch cubes or pieces. Consistency in size is arguably the most critical factor for success – it ensures all pieces cook through at approximately the same rate, preventing scenarios where some bits are burnt while others are still hard.
3. Initial Seasoning and Coating: Place the prepared carrot and potato cubes into a large mixing bowl. Drizzle the 3 tablespoons of olive oil over the vegetables. Sprinkle evenly with the 1 teaspoon of salt, 1/2 teaspoon of black pepper, and the optional 1/2 teaspoon of garlic powder (if using). Use a large spoon or, even better, clean hands to toss everything together thoroughly. Ensure every piece of vegetable is lightly coated with the oil and seasonings. This initial oil coating is vital for facilitating heat transfer and starting the browning process.
4. Arrange for Roasting (Crucial Step): Spread the seasoned vegetables onto the prepared baking sheet in a single layer. Do not overcrowd the pan. The vegetables need space for the hot air to circulate around them. If they are piled up or too close together, they will trap steam, leading to softer, paler, and less flavorful results. You want roasting, not steaming! If your baking sheet is too small to hold all the vegetables in a single layer, use two separate baking sheets. It’s better to use two properly spaced pans than one overcrowded one.
5. First Roasting Phase (Building Tenderness): Place the baking sheet (or sheets) into the fully preheated 400°F (200°C) oven. Roast for 20 minutes. During this initial phase, the vegetables will begin to soften and cook through, and the edges might start to show the first signs of browning.
6. Prepare the Honey-Thyme Glaze: While the vegetables are undergoing their first roast, prepare the glaze. In a small bowl, combine the 3 tablespoons of honey and the 1 tablespoon of chopped fresh thyme leaves (or 1 teaspoon dried). Whisk them together until well combined. If your honey is very thick and difficult to whisk or drizzle, gently warm it for 5-10 seconds in the microwave or in a small saucepan over very low heat just until it becomes more fluid. Be careful not to make it hot.
7. Apply Half the Glaze and Toss: After the initial 20 minutes of roasting, carefully remove the baking sheet from the oven (remember it’s hot!). Drizzle about half of the prepared honey-thyme mixture evenly over the partially cooked vegetables directly on the baking sheet. Use a heatproof spatula to gently toss the carrots and potatoes, turning them over to distribute the glaze as evenly as possible without mashing them. Spreading the glaze now allows it to caramelize without burning during the remaining cooking time.
8. Second Roasting Phase (Caramelization and Finishing): Return the baking sheet to the oven. Continue roasting for another 15 to 25 minutes. The exact time will depend on your specific oven, the actual size of your vegetable pieces, and how caramelized you like them. The goal during this phase is to cook the vegetables until they are completely fork-tender and develop deep golden-brown, caramelized edges. The glaze should thicken slightly and coat the vegetables beautifully.
9. Check for Doneness: Test for doneness by piercing a piece of potato and a piece of carrot with a fork or the tip of a knife. They should slide in easily with little resistance. Look for those desirable dark, crispy edges. If they aren’t quite tender or sufficiently browned after the estimated time, continue roasting for another 5-10 minutes, but keep a close eye on them during these final minutes. The sugars in the honey can go from perfectly caramelized to burnt relatively quickly at this stage.
10. Optional Final Glaze Boost: For an extra layer of glossy shine and a fresh burst of honey-thyme flavor, you can drizzle the remaining half of the glaze over the hot vegetables immediately after removing them from the oven for the final time. Give them one last gentle toss right on the baking sheet or after transferring them to a serving bowl. This step adds a final flourish but is optional if you prefer a slightly less intensely glazed result.
11. Garnish and Serve Immediately: Carefully transfer the hot Honey Glazed Carrots and Potatoes to a warm serving dish or platter. If desired, sprinkle generously with the chopped fresh parsley. The green parsley provides a lovely color contrast and a touch of freshness against the rich colors and flavors of the roasted vegetables. Serve the dish warm as a delicious side to your main course.