Heat the olive oil in a large skillet over medium heat. Add the chicken strips and cook until lightly browned on both sides, about 5 minutes. Remove the chicken to a plate and set aside.
In the same skillet, add the sliced mushrooms and diced onion. Cook until the mushrooms release their liquid and the onion softens, about 6 minutes.
Stir in the minced garlic, flour, paprika, salt, and black pepper. Cook for 1 minute while stirring to coat everything evenly.
Pour in the chicken broth and bring the mixture to a simmer. Let it cook for 3 minutes to thicken slightly.
Return the chicken to the skillet and stir in the sour cream. Simmer gently for another 3 minutes until the chicken is cooked through and the sauce is creamy.
Remove from heat and sprinkle with the chopped parsley before serving.