01 - Preheat the oven to 425°F. Line a large baking sheet with parchment paper or aluminum foil for easy cleanup.
02 - In a large bowl, whisk together the olive oil, minced garlic, lemon zest, lemon juice, dried oregano, dried thyme, smoked paprika, salt, and black pepper until well combined.
03 - Add the chicken thighs, halved baby potatoes, and red onion wedges to the bowl with the marinade. Toss everything thoroughly to ensure the ingredients are evenly coated.
04 - Spread the coated chicken, potatoes, and onion in a single layer on the prepared baking sheet. Ensure the chicken is skin-side up if skin is attached, and pieces are not overcrowded to allow proper roasting.
05 - Place the baking sheet in the preheated oven and roast for 20 minutes to begin cooking the chicken and softening the potatoes.
06 - Carefully remove the baking sheet from the oven. Add the trimmed asparagus to the pan and gently toss with the chicken and potatoes to coat in the rendered juices.
07 - Return the sheet pan to the oven and roast for an additional 15 minutes, or until the chicken is cooked through with an internal temperature of 165°F and the potatoes are golden brown and tender.
08 - Remove the pan from the oven. Garnish the dish with freshly chopped parsley and serve immediately with lemon wedges on the side if desired.