Fresh cracked black pepper, to taste
 PREPARATION:
1. In a bowl, combine oil, Sriracha, pepper, and soy sauce. Marinate steak strips in this mixture for at least 30 minutes.
2. Melt butter in a skillet over medium-high heat. Season steak with salt and pepper and sear quickly, turning just once, until browned, 1–2 minutes. Transfer steak strips to a covered plate and set aside.
3. Reduce heat to medium and cook shallot and garlic in the same skillet, stirring occasionally, until shallot softened and fragrant, about 2 minutes. Add thyme, chives, chili pepper flakes, lemon juice, mustard, and 1/2 cup beef stock, using a wooden spoon to scrape up any browned bits. You can add the remaining of the marinade if you like. Cook, swirling the pan occasionally until the liquid is reduced by about half, about 5 minutes. Add 2 tablespoons butter, swirling the skillet to melt; adjust seasoning pan sauce with salt and pepper.
4. Return the steak to the pan, reheat quickly, and garnish with chopped parsley and chives before serving with a side of sauteed spinach.
Enjoy!