Cook the noodles
Bring a large pot of salted water to a boil and cook the egg noodles according to package instructions. Drain thoroughly and return to the pot. Stir in 2 tablespoons of butter to ensure each noodle is evenly coated and retains a tender, flavorful texture.
Sauté the onions and mushrooms
In a spacious skillet, melt the remaining 2 tablespoons of butter over medium heat. Add the diced onions and sliced mushrooms, cooking for 6–8 minutes until they soften and acquire a golden hue. Stir in the minced garlic and sauté for an additional 30 seconds until aromatic. Season lightly with salt and freshly ground black pepper.
Prepare the sauce
Sprinkle the flour over the vegetables and stir to form a smooth, paste-like coating. Cook for approximately one minute to eliminate any raw flour taste. Gradually incorporate the chicken stock in 1/2-cup increments, stirring continuously to maintain a smooth consistency. Once fully combined, add Worcestershire sauce and adjust seasoning with salt and pepper as needed.
Finish with chicken and sour cream
Allow the sauce to thicken slightly before folding in the shredded rotisserie chicken, ensuring even distribution. Remove the skillet from heat and gently incorporate the sour cream until fully integrated. Taste and adjust seasoning as desired. Return the skillet to low heat briefly to bring the dish to serving temperature, taking care not to overheat and risk curdling the sour cream.
Serve
Stroganoff can be served by either tossing the noodles directly with the sauce or plating the noodles separately and ladling the sauce over the top. Garnish each serving with fresh parsley for an appealing presentation.
Storage
For optimal freshness, store the noodles and sauce separately. Reheat the sauce gently in a skillet, adding a splash of water or chicken stock to preserve its creamy consistency. Warm the noodles in the microwave with a small amount of water before combining. Properly stored, leftovers will remain delicious for several days.