Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Dice the yellow potato into 1-inch cubes, ensuring they are uniform in size for even roasting.
Place the chicken thigh, drumstick, and potato cubes on the prepared baking sheet.
Drizzle with 0.25 tbsp of olive oil and sprinkle with half of the oregano, garlic powder, sea salt, and black pepper.
Toss the potatoes to coat and roast in the oven for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F.
While the chicken roasts, chop the cucumber, celery, and cherry tomatoes into bite-sized pieces.
In a medium mixing bowl, combine the chopped vegetables with the rinsed and drained chickpeas.
Whisk together the remaining 0.25 tbsp of olive oil, lemon juice, and the rest of the spices to create a light vinaigrette.
Toss the vegetable and chickpea mixture with the dressing until well combined.
Serve the hot roasted chicken and potatoes alongside the refreshing Mediterranean salad.