In a mixing bowl, whisk together Greek yogurt, olive oil, lemon juice, paprika, chili powder, minced garlic, salt, and black pepper until smooth. Add the chicken and toss to coat. Cover and refrigerate for 30 minutes to 4 hours.

Boil salted water and cook baby potatoes for about 10 minutes or until fork-tender. Drain and dry on a paper towel.

Preheat grill or skillet over medium-high heat. Add marinated chicken, cooking for 5-6 minutes per side until internal temperature reaches 165°F (75°C). Let rest for 5 minutes before slicing.

Heat olive oil in a skillet over medium-high heat. Add parboiled baby potatoes, cooking for 10-15 minutes until golden and crispy. Season with salt and pepper.

Mash feta cheese in a bowl. Stir in sour cream, chopped dill, lemon juice, and optional pickles or capers until creamy.

Arrange sliced chicken on a serving dish, drizzling with dill feta cream, and serve alongside crispy baby potatoes.