Heat cooking oil in a skillet over medium heat.

If using onion, add it to the skillet and cook until softened, about 3-4 minutes.

Add the diced chicken thighs and cook, stirring occasionally, until browned on all sides, about 5-7 minutes.

Add the diced potatoes to the skillet. Season with salt, pepper, and dried herbs (if using). Stir to combine.

Reduce heat to medium-low, cover the skillet, and cook for 15-20 minutes, stirring occasionally, until potatoes are tender.

Make two small wells in the potato and chicken mixture. Crack an egg into each well.

Cover again and cook for another 3-5 minutes, or until the egg whites are set but the yolks are still slightly runny (or cooked to your preference).

Dollop the sour cream over the skillet just before serving.