Preheat the oven to 400°F and line a large rimmed baking sheet with parchment paper or lightly oil it.
Make the lemon-garlic marinade: in a small bowl or a jar with a lid combine the lemon juice, lemon zest, olive oil, maple syrup, minced garlic, salt, oregano, and black pepper. Whisk or shake vigorously until emulsified.
Place the potato pieces in a large bowl and toss with about half of the marinade so they’re evenly coated. Spread potatoes in a single layer on one side of the prepared sheet pan. Roast 22 minutes, turning once halfway through so they brown evenly.
While the potatoes begin roasting, reserve 1 tablespoon of the marinade for the asparagus. Put the chicken in a clean bowl, pour the remaining marinade over it and toss to coat. Let the chicken sit at room temperature for about 10 minutes to absorb the flavors.
After the potatoes have roasted 22 minutes, remove the baking sheet from the oven. Use a spatula to create space on the pan; transfer potatoes to one side. Use a slotted spoon to place the marinated chicken pieces in a single layer on the empty side of the sheet (discard any excess pooling marinade).
Toss the asparagus with the reserved tablespoon of marinade, then arrange the spears around the chicken and potatoes on the sheet without overcrowding.
Return the pan to the oven and roast another 15–18 minutes, until the chicken reaches 165°F and the asparagus is tender. If you want extra color, broil for 2–3 minutes at the end, watching closely so nothing burns.
Remove the tray and let the chicken rest 5 minutes before serving to lock in juices. Taste and adjust with a pinch of salt, a grind of pepper, or a squeeze of fresh lemon if desired.