1. Preheat your oven and prepare the baking sheet: Start by preheating your oven to 400 F (200 C). Line a large baking sheet with parchment paper for easy cleanup. This prevents sticking and makes transferring the food a breeze.

2. Combine vegetables and seasoning: In a large bowl, toss the quartered new potatoes, asparagus pieces, and red onion wedges with 2 tablespoons of olive oil, half of the minced garlic, half of the dried oregano, half of the dried thyme, a good pinch of salt, and freshly ground black pepper. Spread these seasoned vegetables in an even layer on one side of your prepared baking sheet.

3. Season the chicken: In the same bowl (no need to wash it!), add the boneless, skinless chicken thighs. Drizzle with the remaining 2 tablespoons of olive oil, the rest of the minced garlic, oregano, and thyme. Squeeze the juice from one lemon over the chicken, then season generously with salt and pepper. Toss to ensure the chicken is well coated.

4. Arrange chicken and lemon slices: Place the seasoned chicken thighs on the other side of the baking sheet, next to the vegetables. Arrange the thin lemon slices over and around the chicken pieces. This adds a beautiful presentation and infuses the chicken with more lemon flavor as it roasts.

5. Roast until cooked through: Transfer the baking sheet to the preheated oven and roast for 30-35 minutes. The chicken should be cooked through, reaching an internal temperature of 165 F (74 C), and the vegetables should be tender and slightly caramelized. The lemon slices will also become slightly browned and fragrant.

6. Check for doneness and serve: To ensure the chicken is fully cooked, you can use an instant-read thermometer. The potatoes should be fork-tender. Once everything is perfectly roasted, remove the baking sheet from the oven. Garnish with fresh chopped parsley, if desired, for a pop of color and freshness. Serve immediately.