Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Scrub the Yukon Gold potato and dice it into half-inch cubes, then place them on one side of the prepared baking sheet.
Pat the chicken breast dry and place it on the other side of the sheet next to the potatoes.
In a small bowl, whisk together the extra virgin olive oil, minced garlic, juice from the half lemon, dried oregano, sea salt, and black pepper.
Drizzle half of the lemon-garlic dressing over the chicken and potatoes, tossing the potatoes with a spatula to ensure they are evenly coated.
Roast in the center of the oven for 15 minutes.
While the chicken is roasting, remove the tough stems from the kale and tear the leaves into bite-sized pieces.
Remove the baking sheet from the oven, add the kale to the center of the tray, and drizzle with the remaining dressing.
Toss the kale lightly and return the tray to the oven for another 8 to 10 minutes until the chicken reaches an internal temperature of 165°F and the kale is slightly crisp.