Preheat your oven to 400°F (200°C) and line a large rimmed sheet pan with parchment paper for easy cleanup.
Wash and halve the baby potatoes so they are uniform in size to ensure even roasting.
Slice the chicken breast into 1-inch thick strips or bite-sized pieces.
Trim the woody ends off the asparagus spears and cut them into 2-inch lengths.
In a large mixing bowl, combine the chicken, potatoes, and asparagus with the olive oil, dried oregano, garlic powder, sea salt, and black pepper.
Toss everything thoroughly until the ingredients are well-coated in the oil and spices.
Spread the mixture out in a single layer on the prepared sheet pan, making sure not to overcrowd the ingredients so they roast rather than steam.
Place the pan in the oven and roast for 20 to 25 minutes, or until the chicken is cooked through and the potatoes are fork-tender and golden.
Remove from the oven and immediately drizzle the fresh lemon juice over the hot chicken and vegetables.
Garnish with the fresh lemon zest and serve warm.