Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Scrub the sweet potato and slice it into uniform 1/2-inch thick fries.
Slice the chicken breast into thin, even strips to ensure they cook at the same rate as the potatoes.
In a bowl, toss the sweet potato fries with olive oil, half of the sea salt, and half of the black pepper.
Season the chicken strips with the garlic powder, dried oregano, and the remaining sea salt and black pepper.
Arrange the sweet potatoes and chicken in a single layer on the baking sheet, ensuring they do not overlap.
Bake for 20 to 25 minutes, flipping halfway through, until the fries are tender and the chicken is golden and cooked through.
While baking, whisk together the Greek yogurt and lemon juice in a small bowl to create a bright dipping sauce.
Serve the warm fries and chicken immediately with the chilled yogurt dip on the side.