3. Once the pan is hot, add the chicken. Cook it for about 5-6 minutes/side or until it’s golden and cooked through (165F). Transfer the chicken to a plate.
4. Reduce the heat to medium, and add in the remaining butter and the onion. Sauté the onion until it’s softened and lightly browned (about 10-15 minutes). Timing will vary depending on how thick you sliced the onion. You may need to turn the heat down further if it seems like it’s burning vs. slowly browning.
5. Stir in the garlic and cook for 30 seconds.
6. Stir in the chicken broth and Worcestershire sauce, and scrape up any brown bits from the bottom of the pan.
7. Stir in the sour cream until you’ve got a smooth sauce, and let it heat through for a couple of minutes (ensure it doesn’t bubble too much or else it could curdle).
8. Add the chicken back to the skillet and spoon some sauce over top. Season with extra salt & pepper if needed, and serve immediately with some chopped parsley sprinkled over top.