In a bowl mix olive oil, minced garlic, lemon juice, oregano, paprika, black pepper, and salt.
Add the chicken thighs and coat them well in the marinade.
Let the chicken marinate for at least 30 minutes for better flavor.
Preheat the grill or grill pan over medium heat.
Place the chicken thighs on the grill.
Cook for about 6–7 minutes on one side until golden and lightly charred.
Flip and cook another 6–7 minutes until fully cooked.
In another bowl mix Greek yogurt, grated cucumber, dill, and lemon juice to make tzatziki.
Stir the sauce until smooth and creamy.
Serve the grilled chicken with a generous spoon of tzatziki on top.