1. Place the steaks in the freezer in a single layer for 30-45 minutes. This will make it easy to slice the steaks into thin strips. Meanwhile, clean and slice the mushrooms. When the steaks are ready, use a sharp knife and slice them as thin as you can. Season with some salt and pepper.
2. Grease a large heavy bottom pan with half of the ghee. Once hot, add the beef slices in a single layer - do not overcrowd the pan. Quickly fry over a medium-high heat until browned from all sides. Remove the slices from the pan and place in a bowl. Set aside for later. Repeat for the remaining slices.
3. Grease the pan with the remaining ghee. Place the chopped onion and minced garlic in the pan and cook until lightly browned and fragrant, for about 2-3 minutes. Add the sliced mushrooms and cook for 3-4 more minutes while stirring occasionally.
4. Add Dijon mustard, paprika, and pour in the chicken broth. Add lemon juice and bring to a boil. Cook for 2-3 minutes. Add the browned beef slices and soured cream. Take off the heat.
5. Finally, add freshly chopped parsley. Eat hot. Can store in the fridge for up to 5 days.