Mix the sliced steak with the soy sauce, garlic, ginger, vinegar and red pepper flakes if using. Set aside to marinate for 15-20 minutes.
Mix the Beef Soup Base with the warm water and set aside.
Heat a large skillet over high heat and add enough coconut oil to coat the pan well. Remove the steak from the marinade - reserving the marinade - and add the steak carefully to the hot pan. Spread it out into a single layer and cook until it begins to brown, about two minutes, then turn the beef and cook about two minutes on the other side. Remove the beef from the pan and set aside.
Add the remaining marinade and the Beef Soup Keto Chow mixture to the pan and heat, stirring to mix in the beefy deliciousness from the bottom of the pan.
Add the broccoli and simmer for about 5 minutes, until the broccoli is tender but still firm. Return the beef to the pan and heat through. Stir in the sesame oil. Taste and season with salt and pepper if desired.
Garnish with sliced green onions and sesame seeds.
Notes
You can also try sirloin, flat iron, or hanger steak for this recipe.